QUAD 306 revamp - I am in awe!
- By hariharpal
- Solid State
- 126 Replies
Folks, I want to share my journey with Quad 306, in case it might help someone else in the future. Firstly, I am in no way an electronic expert but I have been tinkering around the amplifiers for about 30 years, so I have learnt a few basics along the way.
I acquired a Quad 306 (Revision 2 PCB) from a friend. He was about to dump it in the recycling because one channel was dead and the fact that he had bought a new Marantz amp. It has since been lying around with me for a couple of years. The past month I got an itch to feel the smell of the solder again, so I opened it up to see the internals. I found a few burnt resistors and after doing some research, I replaced the resistors and turned on the amp again. I was amazed to find that's all that was wrong with the other channel, which was now working with no issues. I was also very impressed with the sound quality coming out of it. This made me think if I could improve it further.
The first step was to figure out why the resistors got burnt, but the answer was right in front of me in the Quad 306 service manual. Page 10, note (C) - "The centre-tapped DC Line is floating and some faults may cause this to shift putting up to 80v on one side possibly damaging R30/R31 (2K2ohm)." However, I also had R22 (560R) smoked out, not sure why.
So after replacing every single resistor with better-specked Vishay resistors and doing some upgrades, I am gobsmacked with how good this thing sounds. I am literally in awe and just in love with it. Here is the list of things I have done;
I noticed, since putting Schottky diodes across the main capacitors the amp doesn't heat up much at all. It has most certainly brought the working temperatures down a lot. At low volumes, it doesn't even get warm and stays cold to the touch. I can have the amp running for hours and it barely gets warm. Whereas before it use to get quite a bit warm/hot to the touch. The difference in heat reduction is huge.
Few warnings for anyone who might be working on these little gems
All in all, I am still in shock by how good this amp sounds, I am hearing instruments in the songs, which I didn't even know existed before. Now I am wondering if my crappy speakers sound so good with it, how would it sound with decent quality speakers. Looks like it's about time to DIY a 2-way speaker system. This is it, folks, I thought I might share my results just in case it might help anyone else here. Happy DIYing and thanks to you all who contribute to the forums, it helps the likes of me (Civil Engineer by profession but with a DIY audio bug).
I acquired a Quad 306 (Revision 2 PCB) from a friend. He was about to dump it in the recycling because one channel was dead and the fact that he had bought a new Marantz amp. It has since been lying around with me for a couple of years. The past month I got an itch to feel the smell of the solder again, so I opened it up to see the internals. I found a few burnt resistors and after doing some research, I replaced the resistors and turned on the amp again. I was amazed to find that's all that was wrong with the other channel, which was now working with no issues. I was also very impressed with the sound quality coming out of it. This made me think if I could improve it further.
The first step was to figure out why the resistors got burnt, but the answer was right in front of me in the Quad 306 service manual. Page 10, note (C) - "The centre-tapped DC Line is floating and some faults may cause this to shift putting up to 80v on one side possibly damaging R30/R31 (2K2ohm)." However, I also had R22 (560R) smoked out, not sure why.
So after replacing every single resistor with better-specked Vishay resistors and doing some upgrades, I am gobsmacked with how good this thing sounds. I am literally in awe and just in love with it. Here is the list of things I have done;
- Main power capacitors upgraded to 6800uf 63v, bypassed by 0.1uf Panasonic film capacitors.
- Replace the rectifier bridge with GBU604 (Strictly speaking, not required)
- Bypass rectifier bridge outputs with 0.1uf 250v Panasonic capacitors to reduce high-frequency noise and diode ringing (TI - Power supply design guidance)
- Put a Schottky diode across the main power supply capacitors to clamp down the ground ( LesW - Quad 306, Pink Fish Media post)
- Put a 22uf decoupling capacitor across zener diode D1, and D2 to filter the power supply to TLC271 ( LesW - Quad 306, Pink Fish Media post)
- Put a 100nf decoupling capacitor across zener diodes D3 and D4. (Dada upgrade guidance)
- Replace the existing 120k R6 resistor with 62k resistor (Dada upgrade guidance)
- Replace the existing 9R1 resistor R13 to 27R resistor to change input sensitivity to 1.0V (Dada upgrade guidance)
- Replace existing 47uf capacitor C7 with 100uf 63v capacitor (Dada upgrade guidance)
- Capacitors C1, C4, C5, and C6 were replaced like for like with polystyrene capacitors. (Dada upgrade guidance)
- C2 replaced with 330nF and C3 replaced with 1uf MKT capacitors (Dada upgrade guidance)
- Capacitor C8 47p Silver mica was replaced with a brand new Silver mica capacitor, like for like. (Dada upgrade recommends polystyrene here)
- Replaced all zener diodes and 1n4003 with the latest versions like for like.
- Replaced TLC271 with a newer version. TLC271CP (original) is rated at 0 to 70 degrees temperature and TLC271IP is rated at -40 to 85 degrees temperature. For the price of another 2 euros, I thought why not. Plus after 25-30 years of technological improvements, I am sure the latest ones are better in every aspect of performance, even when working as a DC servo.
I noticed, since putting Schottky diodes across the main capacitors the amp doesn't heat up much at all. It has most certainly brought the working temperatures down a lot. At low volumes, it doesn't even get warm and stays cold to the touch. I can have the amp running for hours and it barely gets warm. Whereas before it use to get quite a bit warm/hot to the touch. The difference in heat reduction is huge.
Few warnings for anyone who might be working on these little gems
- There are different revisions to the PCB and minor improvements along the way. Check the PCB revision and the corresponding schematics before you tweak any values.
- On the Revision 2 PCB the marked direction of the diode D2 is incorrect, so be careful. On Revision 3 PCB this was corrected.
- R12 is marked as 2K2 on schematics, but 330 ohms is installed. On Revision 3 schematics this was corrected to show 330 ohms.
- Use Quad 306 schematics as guidance only and double-check the value of resistors installed in the amp. Replace like for like.
- After doing these upgrades/changes the T3 emitter voltage is about 60mV (schematics look for 16mV)
- TLC271 output on schematics is looking for -111v but I am getting -20mV and - 5mV here. This is normal and fine, please read the explanation by @Rupopulles in the comments below.
All in all, I am still in shock by how good this amp sounds, I am hearing instruments in the songs, which I didn't even know existed before. Now I am wondering if my crappy speakers sound so good with it, how would it sound with decent quality speakers. Looks like it's about time to DIY a 2-way speaker system. This is it, folks, I thought I might share my results just in case it might help anyone else here. Happy DIYing and thanks to you all who contribute to the forums, it helps the likes of me (Civil Engineer by profession but with a DIY audio bug).
Attachments
Magnetic Reed Switch. Identifying original state
- By Earths
- Everything Else
- 4 Replies
Hi, vintage inquiry here...
Magnetic Reed Switches:
Single Pole, Double Throw.
The common lead toggles between two contacts:
Normally Open (N.O.) and Normally Closed (N.C., longer lead).
image example only
On the dual throw part of the above magnetic reed switch;
The through metal leg is Normally Open
The compound metal leg is Normally Closed
Common contact, the switcher (out of pic)
IF this corresponds to the broken one in the image below it would mean that the long lead would be N.C. and the shorter lead would be N.O.
This is the one to identify-
Is there a standard by which the N.C and N.O. are attributed to a length of leg?
E.G. Lytic Capacitors have the long leg to identify positive.
Coil houses two Magnetic Reed Switches mounted symmetrically. Both failed, one removed, shown below-
This is the circuit that the broken switch was removed from-
BCY70
BC107
100µF
Magnetic Reed Switches:
Single Pole, Double Throw.
The common lead toggles between two contacts:
Normally Open (N.O.) and Normally Closed (N.C., longer lead).
image example only
On the dual throw part of the above magnetic reed switch;
The through metal leg is Normally Open
The compound metal leg is Normally Closed
Common contact, the switcher (out of pic)
IF this corresponds to the broken one in the image below it would mean that the long lead would be N.C. and the shorter lead would be N.O.
This is the one to identify-
Is there a standard by which the N.C and N.O. are attributed to a length of leg?
E.G. Lytic Capacitors have the long leg to identify positive.
Coil houses two Magnetic Reed Switches mounted symmetrically. Both failed, one removed, shown below-
This is the circuit that the broken switch was removed from-
BCY70
BC107
100µF
DIY hFE tester with 1A Ic
- By Preamp
- Equipment & Tools
- 0 Replies
I have built myself a simple hFE tester with a somewhat elevated collector current, compared to the usual suspects (Multimeter, Peak DCA75, etc. running only a couple milliamps). It is basically just a proof of concept for a more elaborate kind of curve tracer that's still in the making, and not a complete "DIY kit", but I thought I'd share it anyhow. It is not difficult to build, but you'll have to be able to flash an AVR microcontroller. Feel free to hit me up if I can be of any help.
Operation is really simple: put in one or two DUTs (it will hande NPN and PNP at the same time), push the button, and read the result. Easy.
Under the hood, the tester will pull a current of 1024mA (adjustable for calibration) through the emitter for roughly 50µs, sample the voltage drop over a 16 Ohm base resistor (adjustable to trim out tolerances), calculate the resulting hFE and finally display it. The short duration of the current pulse will make sure that the DUT doesn't heat up during testing and thus result in a stable and repeatable result on the display. In fact I can mash the button a dozen times in quick succession and the result will only be off by a single ADC count occasionally, but most of the time it will be spot on. Of course the precision and resolution of the AVR-internal ADC and Vref are limited, and the calculation does not compensate for the base current (so technically it is 1024mA Ie and not Ic), but for picking the best devices from a stash of output transistors it should be good enough.
This is what the operation looks like on the scope. The yellow trace is merely a debug output and something for the scope to trigger on. The first blip shows when the current source is activated for 30µs. On the second blip the CCS gets deactivated and the acquisition of the ADC is started - Sample and Hold takes place just a couple of µs after this, but the ADC conversion takes all the time until the third blip. The cyan trace shows the emitter voltage. As you can see it takes about 15µs after switching on the current source until anything happens there, and the current will keep flowing for another ~30µs after the CCS has been disabled. No need to keep the current active through the full acquisition cycle and cause additional dissipation in the DUT!
The schematic. Nothing overly special here, all jellybean parts. The TL431 with its 2.5V was deliberately chosen as the Vref for the current sources. Since that voltage sits close to the rails, the input common mode range of the opamp has to be up for the task. Using something <=100mV here would have necessitated the use of a rail-to-rail opamp. While the TL074 is actually up for this job on the positive rail only, I'd have to use something like an LM324 for the negative rail. I wanted to make do with a single quad opamp from the parts bin though, so I chose the higher Vref for its ubiquity in case of the 431 and it being safely inside the CM range of pretty much any opamp you might throw at it. A noteworthy (probable) downside is, that the Vgs-on of the used power MOSFETs has to be greater than these 2.5V, or else the CCS won't fully turn off. Fortunately most of the jellybean power MOSFETs apply here, so don't use any fancy logic-level parts.
There are two sets of four matched 10k resistors. I am not sure if you can get away with some randomly chosen 1% parts here and how severely that would affect precision; I have matched mine to be within 10 Ohms each. The whole circuit around the diff-amps might even be simplified, but originally I had intended to use some other voltage than ground to reference them to. That didn't work out as intended though, so I left it that way.
Some photos of my device. Got a little cramped inside the case, but everything fit in. The transformer has two 9V secondaries and existed for half an eternity in my parts bin. The circuit was actually tailored around this thing, exploiting the fact that the raw rectified DC sits somewhere around 14V and thus is safe to use without any further regulator on the analog part (5V for the µC being mandatory of course). This limits the Vce to that same ~14V; increasing it would have made the whole circuit much more complicated. The transformer doesn't have to supply lots of current, as there's no sustained high current demand from the tester.
The ZIP file contains the controller source code, written in assembler, and the compiled HEX file ready to flash. Again, if you want to build this and need any help or advice, feel free to ask me.
Operation is really simple: put in one or two DUTs (it will hande NPN and PNP at the same time), push the button, and read the result. Easy.
Under the hood, the tester will pull a current of 1024mA (adjustable for calibration) through the emitter for roughly 50µs, sample the voltage drop over a 16 Ohm base resistor (adjustable to trim out tolerances), calculate the resulting hFE and finally display it. The short duration of the current pulse will make sure that the DUT doesn't heat up during testing and thus result in a stable and repeatable result on the display. In fact I can mash the button a dozen times in quick succession and the result will only be off by a single ADC count occasionally, but most of the time it will be spot on. Of course the precision and resolution of the AVR-internal ADC and Vref are limited, and the calculation does not compensate for the base current (so technically it is 1024mA Ie and not Ic), but for picking the best devices from a stash of output transistors it should be good enough.
This is what the operation looks like on the scope. The yellow trace is merely a debug output and something for the scope to trigger on. The first blip shows when the current source is activated for 30µs. On the second blip the CCS gets deactivated and the acquisition of the ADC is started - Sample and Hold takes place just a couple of µs after this, but the ADC conversion takes all the time until the third blip. The cyan trace shows the emitter voltage. As you can see it takes about 15µs after switching on the current source until anything happens there, and the current will keep flowing for another ~30µs after the CCS has been disabled. No need to keep the current active through the full acquisition cycle and cause additional dissipation in the DUT!
The schematic. Nothing overly special here, all jellybean parts. The TL431 with its 2.5V was deliberately chosen as the Vref for the current sources. Since that voltage sits close to the rails, the input common mode range of the opamp has to be up for the task. Using something <=100mV here would have necessitated the use of a rail-to-rail opamp. While the TL074 is actually up for this job on the positive rail only, I'd have to use something like an LM324 for the negative rail. I wanted to make do with a single quad opamp from the parts bin though, so I chose the higher Vref for its ubiquity in case of the 431 and it being safely inside the CM range of pretty much any opamp you might throw at it. A noteworthy (probable) downside is, that the Vgs-on of the used power MOSFETs has to be greater than these 2.5V, or else the CCS won't fully turn off. Fortunately most of the jellybean power MOSFETs apply here, so don't use any fancy logic-level parts.
There are two sets of four matched 10k resistors. I am not sure if you can get away with some randomly chosen 1% parts here and how severely that would affect precision; I have matched mine to be within 10 Ohms each. The whole circuit around the diff-amps might even be simplified, but originally I had intended to use some other voltage than ground to reference them to. That didn't work out as intended though, so I left it that way.
Some photos of my device. Got a little cramped inside the case, but everything fit in. The transformer has two 9V secondaries and existed for half an eternity in my parts bin. The circuit was actually tailored around this thing, exploiting the fact that the raw rectified DC sits somewhere around 14V and thus is safe to use without any further regulator on the analog part (5V for the µC being mandatory of course). This limits the Vce to that same ~14V; increasing it would have made the whole circuit much more complicated. The transformer doesn't have to supply lots of current, as there's no sustained high current demand from the tester.
The ZIP file contains the controller source code, written in assembler, and the compiled HEX file ready to flash. Again, if you want to build this and need any help or advice, feel free to ask me.
Question about BF245B
- By franziscko
- Parts
- 46 Replies
Hi everyone.
Please help me because I have a big problem.
I have several jfets like this, I need to build a simple preamp
for guitar and I don't know the correct pin arrangement.
I've tried several times but nothing sounds. Now I fear I have them
damaged all. Can you help me? Is the acronym PH Philips?
Thank you!
Please help me because I have a big problem.
I have several jfets like this, I need to build a simple preamp
for guitar and I don't know the correct pin arrangement.
I've tried several times but nothing sounds. Now I fear I have them
damaged all. Can you help me? Is the acronym PH Philips?
Thank you!
2 Way SB Acoustics, initial feedback
New summer, new build plan: a small 2 way (to be complemented with a subwoofer later). Any input welcome before I start buying parts :-D
Goals:
The cone excursion for SB15MFC30 at 50w is problematic <100 Hz, but then the goal is not to push them, and also complement with a sub asap.
What do you guys think? I'm a n00b at crossover design, but it looks to me like they should be fairly easy to integrate?
I'm attaching FRD and ZMA from specs (extracted with FPGraphTracer) and the part specs.
Goals:
- Small / small-ish
- Low to medium SPL (not near field)
- Detailed mid and high frequencies
- Slow bass roll off @ ~80 hz (for sub integration later)
- Tweeter: SB Acoustics SB26CDC, 4 ohms
- Woofer: SB Acoustics SB15MFC30, 4 ohms
- Passive radiator: SB Acoustics 15FSCR
The cone excursion for SB15MFC30 at 50w is problematic <100 Hz, but then the goal is not to push them, and also complement with a sub asap.
What do you guys think? I'm a n00b at crossover design, but it looks to me like they should be fairly easy to integrate?
I'm attaching FRD and ZMA from specs (extracted with FPGraphTracer) and the part specs.
Modified version of Wayne's BA 2018 linestage
- By Ujang Ojil
- Pass Labs
- 25 Replies
hello everyone, greetings permission to share, hope you like it, thank you
Brian Wilson, Beach Boys founder RIP
- By jackinnj
- The Lounge
- 19 Replies
Certainly the seminal figure of my era:
I can remember their appearance on the Ed Sullivan show. Brian's music reverberated on the AM radios at the swimming pool of my teen summers.
https://www.nytimes.com/2025/06/11/arts/music/brian-wilson-dead.html
Brian Wilson, who as the leader and chief songwriter of the Beach Boys became rock’s poet laureate of surf-and-sun innocence, but also an embodiment of damaged genius through his struggles with mental illness and drugs, has died. He was 82.
His family announced the death on Instagram but did not say where or when he died, or state a cause. In early 2024, after the death of his wife, Melinda Wilson, business representatives for Mr. Wilson were granted a conservatorship by a California state judge, after they asserted that he had “a major neurocognitive disorder” and had been diagnosed with dementia.
On mid-1960s hits like “Surfin’ U.S.A.,” “California Girls” and “Fun, Fun, Fun,” the Beach Boys created a musical counterpart to the myth of Southern California as paradise — a soundtrack of cheerful harmonies and a boogie beat to accompany a lifestyle of youthful leisure. Cars, sex and rolling waves were the only cares.
That vision, manifested in Mr. Wilson’s crystalline vocal arrangements, helped make the Beach Boys the defining American band of the era. During its clean-cut heyday of 1962 to 1966, the group landed 13 singles in the Billboard Top 10. Three of them went to No. 1: “I Get Around,” “Help Me, Rhonda” and “Good Vibrations.”
At the same time, the round-faced, soft-spoken Mr. Wilson — who didn’t surf — became one of pop’s most gifted and idiosyncratic studio auteurs, crafting complex and innovative productions that awed his peers.
“That ear,” Bob Dylan once remarked. “I mean, Jesus, he’s got to will that to the Smithsonian.”
Mr. Wilson’s masterpiece was the 1966 album “Pet Sounds,” a wistful song cycle that he directed in elaborate recording sessions, blending the sound of a rock band with classical instrumentation and oddities like the Electro-Theremin, whose otherworldly whistle Mr. Wilson would use again on “Good Vibrations.”
“Pet Sounds” was a commercial disappointment upon its release, but the technical sophistication and melancholic depth of tracks like “God Only Knows” and “I Just Wasn’t Made for These Times” eventually led critics and fellow musicians to honor it as an epochal achievement. In both 2003 and 2020, Rolling Stone ranked “Pet Sounds” No. 2 on its list of the greatest albums of all time. (No. 1 was the Beatles’ “Sgt. Pepper’s Lonely Hearts Club Band” in 2003, Marvin Gaye’s “What’s Going On” in 2020.)
Hailed as a master hitmaker while in his early 20s, Mr. Wilson soon showed signs of instability. Some of his behavior, like placing his piano in a giant sandbox inside his Hollywood Hills home, might have seemed the foibles of a coddled celebrity.
Brian Wilson: 12 Essential Songs
June 11, 2025
But in following up “Pet Sounds,” he stumbled. Over months of sessions for an album he intended to call “Smile,” Mr. Wilson indulged his every eccentricity, no matter how expensive or fruitless, and his growing drug habit fueled paranoia and delusion. Recording a song called “Fire,” he outfitted studio musicians in toy firefighters’ helmets and placed a smoldering bucket in their midst. When he later learned that a nearby building had burned down at about the same time as that session, he scrapped the track, spooked by the thought that his studio “witchcraft” was responsible.
Abandoned by Mr. Wilson, “Smile” entered rock lore as a lost document of a brilliant but troubled mind. Mike Love, the Beach Boys vocalist and longtime foil of Mr. Wilson’s, called it “a whole album of Brian’s madness.” It remained unfinished for nearly 40 years.
“And how did you come up with so many hits? How did the Beach Boys do it?” “Well, we, we just kept plugging away, kept trying, and we went through a bad period. We fought through it, and then we jump onto a new one.” “It means, it just means that I’m an icon. An icon.” “I started out with, like, I think. Doo doo doo doo doo doo, California girls, you know? That’s how I wrote that. First with a bass line, then the chords, then the melody and then the lyrics after that.”
Brian Wilson, leader and chief songwriter of The Beach Boys, wrote several hits in the 1960s, a musical counterpart to the myth of Southern California as paradise.CreditCredit...Paul Natkin for The New York Times
“I had a helluva time getting through some of the frustrations that go along with being a successful record artist,” Mr. Wilson told The New York Times Magazine in 1988. “When I got out there with the Beach Boys, at first I was OK, because I was riding a wave, riding a crest. But then, later on, 10 years later, I got scared, and I got lost, and I was eating caramel sundaes for breakfast. I was all out of whack!”
After “Good Vibrations” in 1966, the band did not have another No. 1 single until “Kokomo” in 1988, which was made without Mr. Wilson’s involvement.
Mr. Wilson’s life story came to be portrayed as a struggle to escape from the yokes of two men: his abusive father and a controlling psychotherapist, Eugene Landy. Mr. Landy’s unorthodox methods, which included monitoring Mr. Wilson 24 hours a day and padlocking his refrigerator, were effective in nursing Mr. Wilson back to health during two periods of treatment in the 1970s and ’80s. Yet Mr. Landy also went into business with his patient, sharing copyrights with Mr. Wilson and taking writing credits on some of his songs.
Image
Mr. Wilson in 1977 with Eugene Landy, his psychotherapist. Mr. Wilson’s life story came to be portrayed as a struggle to escape from the yokes of two men: his abusive father, Murry, and Mr. Landy.Credit...Mark Sullivan/Contour by Getty Images
Mr. Landy eventually came under the scrutiny of the California authorities and surrendered his license. After an intervention by Mr. Wilson’s family, a court order also blocked Mr. Landy from contact with Mr. Wilson.
Mr. Wilson spoke openly about his struggles with mental illness, including his experience with schizoaffective disorder, a condition characterized by hallucinations and delusions. The condition led to the conservatorship granted to his business associates in early 2024.
Starting in the late 1990s, Mr. Wilson undertook a series of concert tours that celebrated his Beach Boys work as a treasure of American song. Onstage, he often sat at the piano with a blank expression, and in public statements he could seem as guileless as one of his melodies.
How The Times decides who gets an obituary. There is no formula, scoring system or checklist in determining the news value of a life. We investigate, research and ask around before settling on our subjects. If you know of someone who might be a candidate for a Times obituary, please suggest it here.
Learn more about our process.
At the Beach Boys’ Rock & Roll Hall of Fame induction in 1988, he described his ambitions: “I wanted to write joyful music that would make other people feel good.”
Brian Douglas Wilson was born on June 20, 1942, in Inglewood, Calif., to Murry and Audree (Korthof) Wilson. His father was a heavy-machinery salesman who had collected a handful of credits as a frustrated songwriter. His mother, a homemaker, kept the Beach Boys’ books in the early days of the band.
The family moved to Hawthorne, another working-class corner of Los Angeles County, when Brian was a toddler, and had two more boys, Dennis and Carl.
From a young age, Brian was almost completely deaf in his right ear. He gave various explanations for the condition, citing a blow from a neighborhood boy or, in some tellings, his father.
Mr. Wilson in Los Angeles in 1965, at the height of his Beach Boys fame. Credit...via Michael Ochs Archives/Getty Images
As a teenager, Brian was a fan of Chuck Berry’s rock ’n’ roll but was especially entranced by the close, melting harmonies of the jazz-influenced vocal group the Four Freshmen; he led his brothers in careful recreations of their songs.
By 1961, the three Wilson boys were playing rock music with Mr. Love, a cousin, and a schoolmate of Brian’s, Al Jardine. In the band’s most familiar early lineup, Brian played bass, Dennis was on the drums, Carl and Mr. Jardine played guitar, and they all sang.
Around that time, Dennis began surfing and delighted in the fashion, trendy lingo and carefree lifestyle that went along with it. One day he told Brian and Mr. Love, “You guys ought to write a song about surfing.”
They did, and that fall, after a rehearsal while the Wilsons’ parents were out of town, the group recorded its first song, “Surfin.’” The young men called themselves the Pendletones, after a type of flannel shirt popular among surfers. When they received the finished record, released by a small local label, Candix, they discovered that they had been renamed the Beach Boys.
“Surfin’” was a crude blueprint for what would become the Beach Boys’ signature sound: a simple lead vocal line (sung by Mr. Love) accompanied by sunny harmonizing, doo-wop-style scatting and a rudimentary rock beat. To that point the surf music fad had primarily involved guitar instrumentals, but by adding vocals the Beach Boys created a wave rider’s credo:
Image
The Beach Boys in 1964. From left, Al Jardine, Mike Love, Dennis Wilson, Brian Wilson and Carl Wilson. Credit...RB/Redferns, via Getty Images
Signed by Capitol Records in 1962, the group was prolific from the start, releasing 10 studio LPs through 1965. With short hair, toothy smiles and matching striped shirts, the young men cut a wholesome image. Their harmonies, shared by all the members, were vivacious and pristine.
Mr. Wilson became the band’s primary producer and songwriter, and his sophistication soon shone through. “Surfer Girl,” a lilting, harmony-drenched ballad that went to No. 7 in 1963, was perhaps the first pop hit written, arranged, produced and sung by the same person.
Mr. Wilson’s first No. 1, however, came as a writer of Jan and Dean’s song “Surf City” (1963). In a sign of conflicts to come, Murry Wilson, who managed the Beach Boys and controlled the band’s songwriting copyrights, was furious that Brian had given a valuable hit to another act.
Other problems surfaced. “Surfin’ U.S.A.” resembled Chuck Berry’s “Sweet Little Sixteen” a bit too closely, so Berry’s name was added to the credits, and his publisher acquired the song’s copyright.
In December 1964, Mr. Wilson married Marilyn Rovell, who sang in a girl group called the Honeys. A few weeks later, just before Christmas, he had a panic attack on a flight to a Beach Boys engagement in Houston and decided to quit touring to concentrate on songwriting and recording.
That same year, the group fired Murry as manager. He responded by promoting a Beach Boys copycat group, the Sunrays, which quickly flamed out.
As Mr. Wilson would recount, his father had long tormented him physically and emotionally. In one form of punishment that Mr. Wilson described many times, his father would remove his glass eye and force his terrified son to stare into the empty socket.
“My dad was violent,” Mr. Wilson wrote in a 2016 memoir, “I Am Brian Wilson,” written with Ben Greenman. “He was cruel.”
Freed from his father’s control and the Beach Boys’ touring demands, Mr. Wilson immersed himself in the studio. For a time, he embodied the role of a visionary working within the confines of commercial pop, much like the producer Phil Spector, Mr. Wilson’s hero.
Image
The Beach Boys performed on “The Ed Sullivan Show” in September 1964.Credit...CBS Photo Archives, via Getty Images
“Pet Sounds,” released in May 1966, elevated the Beach Boys’ music to a level far above anything they had created before. With the rest of the group on the road, Mr. Wilson made the album primarily with studio musicians, and he employed a broad sonic palette: French horns, strings, timpani and playful sound effects like bicycle bells, all in addition to the standard rock complement of guitar, bass and drums.
Songs like “Wouldn’t It Be Nice” and “Caroline, No” explored themes of lost innocence and the transition to adulthood. Most were written with Tony Asher, a young lyricist and jingle writer whom Mr. Wilson had recently met. Mr. Wilson took painstaking care with every detail of the recording, including lushly arranged stacks of vocal harmonies, which for the other Beach Boys often meant an excruciating number of takes. Mr. Love called him “the Stalin of the studio,” only half in jest.
Upon release, the album stalled at No. 10, a relative dud by Beach Boys standards. By then, however, Mr. Wilson was already working on his next gem: the single “Good Vibrations.”
Spliced together from months of sessions across four studios — according to Mr. Love, the group recorded 25 to 30 vocal overdubs for a segment that lasted just five seconds — “Good Vibrations” was a catchy and sonically adventurous invocation of peppy West Coast spirituality. Released in October 1966, the song became an indelible radio hit, but it was Mr. Wilson’s last moment at the vanguard of pop.
Yet the album collapsed after more than 80 sessions in 1966 and 1967. To meet their obligations to Capitol, the Beach Boys quickly assembled two albums in late 1967 — “Smiley Smile,” a scaled-down version of Mr. Wilson’s opus, and “Wild Honey” — which had little impact.
For years thereafter, the group was adrift. The Beach Boys were caught between the new vogues of heavy rock and folk-influenced singer-songwriters, and their albums sold modestly at best. Mr. Wilson was withdrawn, spending long stretches in bed and obsessively listening to old records like the Ronettes’ “Be My Baby,” Phil Spector’s masterpiece from 1963.
Mr. Wilson’s drug use, which had begun during happier times for the band — the buoyant 1965 hit “California Girls,” he said, was written after an acid trip — had grown out of control, stunting his creativity. “I lost interest in writing songs,” Mr. Wilson once told Rolling Stone. “I lost the inspiration. I was too concerned with getting drugs to write songs.”
Some Beach Boys albums, like “Surf’s Up” (1971) and “Holland” (1973), released by the band’s new label, Reprise, still had a spark of invention.
But the band changed course after Capitol issued “Endless Summer” (1974), a compilation of the group’s early hits, which became the Beach Boys’ second No. 1 album and their first in a decade. Although the band’s live shows had long been packed with old numbers, its next studio album, “15 Big Ones” (1976) — promoted heavily as Mr. Wilson’s
I can remember their appearance on the Ed Sullivan show. Brian's music reverberated on the AM radios at the swimming pool of my teen summers.
https://www.nytimes.com/2025/06/11/arts/music/brian-wilson-dead.html
Brian Wilson, who as the leader and chief songwriter of the Beach Boys became rock’s poet laureate of surf-and-sun innocence, but also an embodiment of damaged genius through his struggles with mental illness and drugs, has died. He was 82.
His family announced the death on Instagram but did not say where or when he died, or state a cause. In early 2024, after the death of his wife, Melinda Wilson, business representatives for Mr. Wilson were granted a conservatorship by a California state judge, after they asserted that he had “a major neurocognitive disorder” and had been diagnosed with dementia.
On mid-1960s hits like “Surfin’ U.S.A.,” “California Girls” and “Fun, Fun, Fun,” the Beach Boys created a musical counterpart to the myth of Southern California as paradise — a soundtrack of cheerful harmonies and a boogie beat to accompany a lifestyle of youthful leisure. Cars, sex and rolling waves were the only cares.
That vision, manifested in Mr. Wilson’s crystalline vocal arrangements, helped make the Beach Boys the defining American band of the era. During its clean-cut heyday of 1962 to 1966, the group landed 13 singles in the Billboard Top 10. Three of them went to No. 1: “I Get Around,” “Help Me, Rhonda” and “Good Vibrations.”
At the same time, the round-faced, soft-spoken Mr. Wilson — who didn’t surf — became one of pop’s most gifted and idiosyncratic studio auteurs, crafting complex and innovative productions that awed his peers.
“That ear,” Bob Dylan once remarked. “I mean, Jesus, he’s got to will that to the Smithsonian.”
Mr. Wilson’s masterpiece was the 1966 album “Pet Sounds,” a wistful song cycle that he directed in elaborate recording sessions, blending the sound of a rock band with classical instrumentation and oddities like the Electro-Theremin, whose otherworldly whistle Mr. Wilson would use again on “Good Vibrations.”
“Pet Sounds” was a commercial disappointment upon its release, but the technical sophistication and melancholic depth of tracks like “God Only Knows” and “I Just Wasn’t Made for These Times” eventually led critics and fellow musicians to honor it as an epochal achievement. In both 2003 and 2020, Rolling Stone ranked “Pet Sounds” No. 2 on its list of the greatest albums of all time. (No. 1 was the Beatles’ “Sgt. Pepper’s Lonely Hearts Club Band” in 2003, Marvin Gaye’s “What’s Going On” in 2020.)
“It was ‘Pet Sounds’ that blew me out of the water,” Paul McCartney once said. “I figure no one is educated musically ’til they’ve heard that album.”
Hailed as a master hitmaker while in his early 20s, Mr. Wilson soon showed signs of instability. Some of his behavior, like placing his piano in a giant sandbox inside his Hollywood Hills home, might have seemed the foibles of a coddled celebrity.
Brian Wilson: 12 Essential Songs
June 11, 2025
But in following up “Pet Sounds,” he stumbled. Over months of sessions for an album he intended to call “Smile,” Mr. Wilson indulged his every eccentricity, no matter how expensive or fruitless, and his growing drug habit fueled paranoia and delusion. Recording a song called “Fire,” he outfitted studio musicians in toy firefighters’ helmets and placed a smoldering bucket in their midst. When he later learned that a nearby building had burned down at about the same time as that session, he scrapped the track, spooked by the thought that his studio “witchcraft” was responsible.
Abandoned by Mr. Wilson, “Smile” entered rock lore as a lost document of a brilliant but troubled mind. Mike Love, the Beach Boys vocalist and longtime foil of Mr. Wilson’s, called it “a whole album of Brian’s madness.” It remained unfinished for nearly 40 years.
“And how did you come up with so many hits? How did the Beach Boys do it?” “Well, we, we just kept plugging away, kept trying, and we went through a bad period. We fought through it, and then we jump onto a new one.” “It means, it just means that I’m an icon. An icon.” “I started out with, like, I think. Doo doo doo doo doo doo, California girls, you know? That’s how I wrote that. First with a bass line, then the chords, then the melody and then the lyrics after that.”
Brian Wilson, leader and chief songwriter of The Beach Boys, wrote several hits in the 1960s, a musical counterpart to the myth of Southern California as paradise.CreditCredit...Paul Natkin for The New York Times
“I had a helluva time getting through some of the frustrations that go along with being a successful record artist,” Mr. Wilson told The New York Times Magazine in 1988. “When I got out there with the Beach Boys, at first I was OK, because I was riding a wave, riding a crest. But then, later on, 10 years later, I got scared, and I got lost, and I was eating caramel sundaes for breakfast. I was all out of whack!”
After “Good Vibrations” in 1966, the band did not have another No. 1 single until “Kokomo” in 1988, which was made without Mr. Wilson’s involvement.
Mr. Wilson’s life story came to be portrayed as a struggle to escape from the yokes of two men: his abusive father and a controlling psychotherapist, Eugene Landy. Mr. Landy’s unorthodox methods, which included monitoring Mr. Wilson 24 hours a day and padlocking his refrigerator, were effective in nursing Mr. Wilson back to health during two periods of treatment in the 1970s and ’80s. Yet Mr. Landy also went into business with his patient, sharing copyrights with Mr. Wilson and taking writing credits on some of his songs.
Image
Mr. Wilson in 1977 with Eugene Landy, his psychotherapist. Mr. Wilson’s life story came to be portrayed as a struggle to escape from the yokes of two men: his abusive father, Murry, and Mr. Landy.Credit...Mark Sullivan/Contour by Getty Images
Mr. Landy eventually came under the scrutiny of the California authorities and surrendered his license. After an intervention by Mr. Wilson’s family, a court order also blocked Mr. Landy from contact with Mr. Wilson.
Mr. Wilson spoke openly about his struggles with mental illness, including his experience with schizoaffective disorder, a condition characterized by hallucinations and delusions. The condition led to the conservatorship granted to his business associates in early 2024.
Starting in the late 1990s, Mr. Wilson undertook a series of concert tours that celebrated his Beach Boys work as a treasure of American song. Onstage, he often sat at the piano with a blank expression, and in public statements he could seem as guileless as one of his melodies.
How The Times decides who gets an obituary. There is no formula, scoring system or checklist in determining the news value of a life. We investigate, research and ask around before settling on our subjects. If you know of someone who might be a candidate for a Times obituary, please suggest it here.
Learn more about our process.
At the Beach Boys’ Rock & Roll Hall of Fame induction in 1988, he described his ambitions: “I wanted to write joyful music that would make other people feel good.”
Brian Douglas Wilson was born on June 20, 1942, in Inglewood, Calif., to Murry and Audree (Korthof) Wilson. His father was a heavy-machinery salesman who had collected a handful of credits as a frustrated songwriter. His mother, a homemaker, kept the Beach Boys’ books in the early days of the band.
The family moved to Hawthorne, another working-class corner of Los Angeles County, when Brian was a toddler, and had two more boys, Dennis and Carl.
From a young age, Brian was almost completely deaf in his right ear. He gave various explanations for the condition, citing a blow from a neighborhood boy or, in some tellings, his father.
Mr. Wilson in Los Angeles in 1965, at the height of his Beach Boys fame. Credit...via Michael Ochs Archives/Getty Images
As a teenager, Brian was a fan of Chuck Berry’s rock ’n’ roll but was especially entranced by the close, melting harmonies of the jazz-influenced vocal group the Four Freshmen; he led his brothers in careful recreations of their songs.
By 1961, the three Wilson boys were playing rock music with Mr. Love, a cousin, and a schoolmate of Brian’s, Al Jardine. In the band’s most familiar early lineup, Brian played bass, Dennis was on the drums, Carl and Mr. Jardine played guitar, and they all sang.
Around that time, Dennis began surfing and delighted in the fashion, trendy lingo and carefree lifestyle that went along with it. One day he told Brian and Mr. Love, “You guys ought to write a song about surfing.”
They did, and that fall, after a rehearsal while the Wilsons’ parents were out of town, the group recorded its first song, “Surfin.’” The young men called themselves the Pendletones, after a type of flannel shirt popular among surfers. When they received the finished record, released by a small local label, Candix, they discovered that they had been renamed the Beach Boys.
“Surfin’” was a crude blueprint for what would become the Beach Boys’ signature sound: a simple lead vocal line (sung by Mr. Love) accompanied by sunny harmonizing, doo-wop-style scatting and a rudimentary rock beat. To that point the surf music fad had primarily involved guitar instrumentals, but by adding vocals the Beach Boys created a wave rider’s credo:
Though Mr. Wilson embraced the youthful freedom that surfing represented, he never took to the sport. “I tried it once and got conked on the head with the board,” he once said.
Image
The Beach Boys in 1964. From left, Al Jardine, Mike Love, Dennis Wilson, Brian Wilson and Carl Wilson. Credit...RB/Redferns, via Getty Images
Signed by Capitol Records in 1962, the group was prolific from the start, releasing 10 studio LPs through 1965. With short hair, toothy smiles and matching striped shirts, the young men cut a wholesome image. Their harmonies, shared by all the members, were vivacious and pristine.
Mr. Wilson became the band’s primary producer and songwriter, and his sophistication soon shone through. “Surfer Girl,” a lilting, harmony-drenched ballad that went to No. 7 in 1963, was perhaps the first pop hit written, arranged, produced and sung by the same person.
Mr. Wilson’s first No. 1, however, came as a writer of Jan and Dean’s song “Surf City” (1963). In a sign of conflicts to come, Murry Wilson, who managed the Beach Boys and controlled the band’s songwriting copyrights, was furious that Brian had given a valuable hit to another act.
Other problems surfaced. “Surfin’ U.S.A.” resembled Chuck Berry’s “Sweet Little Sixteen” a bit too closely, so Berry’s name was added to the credits, and his publisher acquired the song’s copyright.
In December 1964, Mr. Wilson married Marilyn Rovell, who sang in a girl group called the Honeys. A few weeks later, just before Christmas, he had a panic attack on a flight to a Beach Boys engagement in Houston and decided to quit touring to concentrate on songwriting and recording.
That same year, the group fired Murry as manager. He responded by promoting a Beach Boys copycat group, the Sunrays, which quickly flamed out.
As Mr. Wilson would recount, his father had long tormented him physically and emotionally. In one form of punishment that Mr. Wilson described many times, his father would remove his glass eye and force his terrified son to stare into the empty socket.
“My dad was violent,” Mr. Wilson wrote in a 2016 memoir, “I Am Brian Wilson,” written with Ben Greenman. “He was cruel.”
Freed from his father’s control and the Beach Boys’ touring demands, Mr. Wilson immersed himself in the studio. For a time, he embodied the role of a visionary working within the confines of commercial pop, much like the producer Phil Spector, Mr. Wilson’s hero.
Image
The Beach Boys performed on “The Ed Sullivan Show” in September 1964.Credit...CBS Photo Archives, via Getty Images
“Pet Sounds,” released in May 1966, elevated the Beach Boys’ music to a level far above anything they had created before. With the rest of the group on the road, Mr. Wilson made the album primarily with studio musicians, and he employed a broad sonic palette: French horns, strings, timpani and playful sound effects like bicycle bells, all in addition to the standard rock complement of guitar, bass and drums.
Songs like “Wouldn’t It Be Nice” and “Caroline, No” explored themes of lost innocence and the transition to adulthood. Most were written with Tony Asher, a young lyricist and jingle writer whom Mr. Wilson had recently met. Mr. Wilson took painstaking care with every detail of the recording, including lushly arranged stacks of vocal harmonies, which for the other Beach Boys often meant an excruciating number of takes. Mr. Love called him “the Stalin of the studio,” only half in jest.
Upon release, the album stalled at No. 10, a relative dud by Beach Boys standards. By then, however, Mr. Wilson was already working on his next gem: the single “Good Vibrations.”
Spliced together from months of sessions across four studios — according to Mr. Love, the group recorded 25 to 30 vocal overdubs for a segment that lasted just five seconds — “Good Vibrations” was a catchy and sonically adventurous invocation of peppy West Coast spirituality. Released in October 1966, the song became an indelible radio hit, but it was Mr. Wilson’s last moment at the vanguard of pop.
In Thrall
“Smile,” Mr. Wilson’s next album project, which he made with another songwriting collaborator, Van Dyke Parks, was intended to be his supreme achievement. Mr. Wilson hyped it at the time as “a teenage symphony to God.”Yet the album collapsed after more than 80 sessions in 1966 and 1967. To meet their obligations to Capitol, the Beach Boys quickly assembled two albums in late 1967 — “Smiley Smile,” a scaled-down version of Mr. Wilson’s opus, and “Wild Honey” — which had little impact.
For years thereafter, the group was adrift. The Beach Boys were caught between the new vogues of heavy rock and folk-influenced singer-songwriters, and their albums sold modestly at best. Mr. Wilson was withdrawn, spending long stretches in bed and obsessively listening to old records like the Ronettes’ “Be My Baby,” Phil Spector’s masterpiece from 1963.
Mr. Wilson’s drug use, which had begun during happier times for the band — the buoyant 1965 hit “California Girls,” he said, was written after an acid trip — had grown out of control, stunting his creativity. “I lost interest in writing songs,” Mr. Wilson once told Rolling Stone. “I lost the inspiration. I was too concerned with getting drugs to write songs.”
Some Beach Boys albums, like “Surf’s Up” (1971) and “Holland” (1973), released by the band’s new label, Reprise, still had a spark of invention.
But the band changed course after Capitol issued “Endless Summer” (1974), a compilation of the group’s early hits, which became the Beach Boys’ second No. 1 album and their first in a decade. Although the band’s live shows had long been packed with old numbers, its next studio album, “15 Big Ones” (1976) — promoted heavily as Mr. Wilson’s
CamillaDSP - Cross-platform IIR and FIR engine for crossovers, room correction etc
- PC Based
- 6096 Replies
I would like to announce CamillaDSP, a general purpose tool for routing and filtering sound. It can be used for example for building crossovers for active speakers, or for performing room correction.
You can find the source code here: GitHub - HEnquist/camilladsp
The documentation for all published versions can be found here: CamillaDSP
There is a second repository for configuration help here: GitHub - HEnquist/camilladsp-config: Help for setting up CamillaDSP, example config files etc
Quick summary
I have been using BruteFIR for crossovers for quite some time, but there were two main things I wanted to improve upon. Firstly BruteFIR only supports FIR filters, and I wanted the ability to also use BiQuad without having to make an overly complicated setup. Secondly when BruteFIR encounters a buffer underrun it always exits with a "broken pipe" error instead of just trying again. This can get somewhat annoying. I also thought that the BruteFIR configuration is unnessecarily complicated.
I have also been using the excellent tool EqualizerAPO that does all I want, but it's for Windows only.
When using Alsa for both input and output, CamillaDSP can work almost as a drop-in replacement for BruteFIR. I run a 2048 tap stereo 2-way crossover at 44.1kHz, and this consumes less than 2% of a single cpu core on my HTPC (dual core Intel Skylake).
To help with configuration CamillaDSP checks the configuration and tries to give helpful error messages when there is a problem. In addition there is a Python script to visualize the whole pipeline from a config file.
Sample output:
To try it, download a pre-built binary for your system from the "Releases" page:. Click "Assets" to view the available files.
Instead of using a pre-built binary it can also be built from source. The "Cargo" tool makes this very easy as it will download and compile all dependencies automatically. See more instructions in the README.
You can find the source code here: GitHub - HEnquist/camilladsp
The documentation for all published versions can be found here: CamillaDSP
There is a second repository for configuration help here: GitHub - HEnquist/camilladsp-config: Help for setting up CamillaDSP, example config files etc
Quick summary
- For Linux, macOS and Windows
- Written in Rust
- IIR filters (BiQuad)
- FIR filters (Convolution via FFT)
- Built-in sample rate converter
- Filters can be chained freely
- Flexible routing
- Alsa, PulseAudio, Wasapi, CoreAudio, File and stdio input/output
- Simple YAML configuration
- All calculations done with 64-bit floats
I have been using BruteFIR for crossovers for quite some time, but there were two main things I wanted to improve upon. Firstly BruteFIR only supports FIR filters, and I wanted the ability to also use BiQuad without having to make an overly complicated setup. Secondly when BruteFIR encounters a buffer underrun it always exits with a "broken pipe" error instead of just trying again. This can get somewhat annoying. I also thought that the BruteFIR configuration is unnessecarily complicated.
I have also been using the excellent tool EqualizerAPO that does all I want, but it's for Windows only.
When using Alsa for both input and output, CamillaDSP can work almost as a drop-in replacement for BruteFIR. I run a 2048 tap stereo 2-way crossover at 44.1kHz, and this consumes less than 2% of a single cpu core on my HTPC (dual core Intel Skylake).
To help with configuration CamillaDSP checks the configuration and tries to give helpful error messages when there is a problem. In addition there is a Python script to visualize the whole pipeline from a config file.
Sample output:
To try it, download a pre-built binary for your system from the "Releases" page:. Click "Assets" to view the available files.
Instead of using a pre-built binary it can also be built from source. The "Cargo" tool makes this very easy as it will download and compile all dependencies automatically. See more instructions in the README.
For Sale Kevin Gilmore Dynalo MK2 Super Symmetry Parts Kit
Also known as the "MultiAmp" on the HeadCase forum where Kevin Gilmore hangs out, this is another project of mine that got shelved due to life happening.
The amp boards are completed, with the opamps and matched Bipolar transistor IC unpopulated(but included).
The GRLV PSU board has been mostly completed, with the missing parts included in the package. Power Transistors were not mounted as my original plan was to mount them to the side panel of a Galaxy Case, so proper heatsinks or mounting to a chassis is required(insulators included). A balanced headphone protector board is also part of the package, as well as various XLR connectors, parts for a Balanced to SE adapter, IEC power connector, and 25VA x 20 Volt Antec transformer.
Also included is a KG designed I2C controlled balanced relay volume control board, with software available on Head-Case
Please see the Thread on the Head-Case Diy Forum
$200 US plus shipping TBD depending on Speed and location.
The amp boards are completed, with the opamps and matched Bipolar transistor IC unpopulated(but included).
The GRLV PSU board has been mostly completed, with the missing parts included in the package. Power Transistors were not mounted as my original plan was to mount them to the side panel of a Galaxy Case, so proper heatsinks or mounting to a chassis is required(insulators included). A balanced headphone protector board is also part of the package, as well as various XLR connectors, parts for a Balanced to SE adapter, IEC power connector, and 25VA x 20 Volt Antec transformer.
Also included is a KG designed I2C controlled balanced relay volume control board, with software available on Head-Case
Please see the Thread on the Head-Case Diy Forum
$200 US plus shipping TBD depending on Speed and location.
Attachments
Rollover - A Decent Amplifier with JFET in and MOSFET out
- By lineup
- Solid State
- 25 Replies
Uses LSK189 for input.
Buy at mouser.com: https://www2.mouser.com/ProductDetail/Linear-Integrated-Systems/LSK189-TO-92-3L-BK?qs=T%2BzbugeAwjjUrS49wFak%2Bw==
Uses ECX10N20 and ECX10P20 for output.
Buy for example at: https://gb.profusion.uk/uk/audio/transist/lateral-mosfets
The input JFET pair can be other JFET, too.
Bias in output is set to 300mA.
THD is 0.00020% with the LSK189.
Buy at mouser.com: https://www2.mouser.com/ProductDetail/Linear-Integrated-Systems/LSK189-TO-92-3L-BK?qs=T%2BzbugeAwjjUrS49wFak%2Bw==
Uses ECX10N20 and ECX10P20 for output.
Buy for example at: https://gb.profusion.uk/uk/audio/transist/lateral-mosfets
The input JFET pair can be other JFET, too.
Bias in output is set to 300mA.
THD is 0.00020% with the LSK189.
Taramps TS2000x4 confirm channel dependency
I’ve recently repaired this amp but I find an occurrence I want to confirm, IRFB5620 are the output and a cross of IRFB4227 was referred as sub, after installed they got hot and no drive waveform, I swapped to another working channel and still warmed. Nothing else was damaged in the amp just one bad output. It was when I purchased the IRFB5620 then the amp worked.
Another puzzling problem is whenever I pulled the output from any one channel, the adjoining channel won’t produce any waveform regardless of four “independent seeming” channels (that is 1 or 2 and 3 or 4). Therefore, if one channel goes bad there is no three channels (like class AB) even if you remove the damaged outputs and free up voltage rails.
Can someone explain?
Another puzzling problem is whenever I pulled the output from any one channel, the adjoining channel won’t produce any waveform regardless of four “independent seeming” channels (that is 1 or 2 and 3 or 4). Therefore, if one channel goes bad there is no three channels (like class AB) even if you remove the damaged outputs and free up voltage rails.
Can someone explain?
Amp Camp Amp - ACA
Looky Here... Original article by Nelson Pass: Amp Camp Amp #1
😀
______________________________________________________
Info for Amp Camp Kit (updated by Moderators)
Here's the ORIGINAL step by step photo build guide: ACA illustrated build guide
A new Build Guide for the V1.6 Two channel Chassis in the diyAudio Store.
Amp Camp Amp V1.6 Build Guide - diyAudio Guides
The small changes of the 1.8 version.All ACA’s that have 2 channels in one chassis can be converted to Version 1.8 which only requires buying a different rear panel switch and some re-wiring of the rear panel. Amp Camp Amp V1.8 Change Information - diyAudio Guides
The link below is to a Step by step build video by Patrick Norton on his TekThing website. He makes an error in cutting out the thermal insulator and leaving the backing on. Thebacking just peels off, no cutting required:
February 2016 Patreon Build Video: Amp Camp Amp Dual Monoblocks! - YouTube
See post #1453 for a tweak to the original V1.0 circuit boards. It’s not essential but should improve the sound. This tweak has been incorporated in subsequent versions (1b & 1.5, 1.6,1.8). if you have those circuit boards or kits it's already added to the board, and the part (R15) included in the kits
An ACA thread with lots of great ideas which may or may not improve the amp to your desires:
ACA amp with premium parts
Here’s a thread discussing the kits from the DiyAudio store for V1.6 and V1.8
Amp Camp Amp Kit 1.6/1.8
And here’s the link to the kits:
https://diyaudiostore.com/collections/kits/products/amp-camp-amp-kit?variant=7072933085218
For Sale AN39- PSU Cap Multiplier - Hiraga le Monstre - Soft Start- DC Blocker- CRC PSU.
Attachments
Folded Cascode CEN IV with fixed Rails
- By EUVL
- Digital Line Level
- 195 Replies
Exactly 11 years and 2250 posts after the original CEN IV, the simple circuit still have many fans and positive feedback.
But the difficulty of having to use floating power supplies remains.
Especially, if one is using 2 channel balanced mode outputs, 4 of these floating supplies are required.
https://www.diyaudio.com/community/...lution-of-a-minimalistic-iv-converter.195483/
The question has been -- is it possible to have at least similar performance but using fixed rails ?
In the original thread, the use of current sources between fixed rail and IV circuit has been discussed.
11 years later, with experience gained from the revised XCEN converter circuit, the puzzle has finally been solved.
So here you are. Happy Reading.
Patrick
.
But the difficulty of having to use floating power supplies remains.
Especially, if one is using 2 channel balanced mode outputs, 4 of these floating supplies are required.
https://www.diyaudio.com/community/...lution-of-a-minimalistic-iv-converter.195483/
The question has been -- is it possible to have at least similar performance but using fixed rails ?
In the original thread, the use of current sources between fixed rail and IV circuit has been discussed.
11 years later, with experience gained from the revised XCEN converter circuit, the puzzle has finally been solved.
So here you are. Happy Reading.
Patrick
.
Limestone turntable, help needed with motor and drive
- By Drbulj
- Analogue Source
- 349 Replies
This is second (and last) blast from the past project that I will publish. Its from early 2000's when I was very much into doing different audio things.
Other of my old projects have no much difference from usually seen executions, so I will skip those.
As elementary school kid (in 1977), my older sister left me her BSR turntable system (in Yugoslavia than called Tosca) and some 50LP's, good stuff of the time, Leonard Cohen, Dylan, Cat Stevens, Janis Joplin, Roberta Flack, Jimmy Smith, some classic and so on... Anyway, I felt in love with LP's and HIFI forever, this still goes on.
Anyway, few friends (actually their parents) had Thorenses, Sondeks and Duals, , I always wanted proper turntable. By the time I made my own money, CD came into play and I bought one of the first Philips CD player.
Few years after I still wanted TT, bought one crappy example, throw it away and decided to make my own. Intention was not to make hi end piece, but to make vintage looking TT similar to those that I was wishing for:
This is the result:
Simple comparison between Hornresp and AKABAK. Beginner's mistake or?
- By Ramsten
- Subwoofers
- 5 Replies
Attachments
Some Single-Battery Guitar Preamps
- Electronic Design
- 66 Replies
Single-Supply Preamps For Guitar
Here are six preamps for guitar using op-amps; each operated from a single 9V battery as the power supply, thus making them suitable for stomp-box applications. Sources for the diagrams are noted with the diagrams. The circuits are faithful to original diagrams but for minor changes, such as the adding of an input level control or the use of a pot in a negative feedback loop to provide the user with a gain control. However, while based on proven designs, these designs must still be considered experimental. Also, the diagrams originally posted had flaws, which were corrected according to advice from forum members here, who I thank for their help. The diagrams shown now are updated versions (but some may be updated again if needed).
The specified IC is the OPA2156 dual low-noise op-amp IC, but an original TI unit can be expensive and may take a long time for delivery. So, I have listed a number of pin-compatible substitutes at the end of this post, all of which will provide good results.
The next circuit features a Baxandall type of 2-band tone-control, followed by one with a Fender-style 2-band control, which works differently from the Baxandall-type, though both leave the mids fixed. For those who prefer three bands, all other circuits below involve 3-band Fender-style tone stacks.
Note the seemingly redundant Tone control at the output below. That is included to provide an additional means of shaping high-end response.
What follows next are the preamps with the 3-band tone-stacks having default Fender Bassman part-values.
Consider the difference in the way the input and output jacks are shown below. This would be a good way to do the foregoing circuits too, but I show this configuration only for the last two circuits. This one also has a fuzz circuit using diodes, providing clipping without having to overdrive op-amps. But if that is desired, an older dual JFET-input IC can be considered, having minimum supply voltage <= 4.5 V, such as the LF353.
The circuit below likewise has a diode-type fuzz circuit, but which is highly adjustable.
Here is the pinout diagram for a dual op-amp, along with pin-compatible example ICs.
ICs listed here should perform satisfactorily for the electric guitar and offer the least noise and distortion for circuits operated using a single 9V battery. They were chosen from among the best op-amps available today but whose minimum supply voltage is <= 4.5 VDC, since half of 9V is 4.5V, and a single-supply circuit sets the zero signal-reference operating-point midway between ground and the supply.
To get more distortion than the diodes provide, by overdriving a given circuit, use the LF353 instead of any of the ICs listed above. It is an older op-amp that will work with a single 9V battery as the supply and is a JFET-input op-amp, which means its overdriven tonality is preferred over that of most non-JFET-input op-amps. However, it will also work fine without being overdriven, and will not drain the battery nearly as fast as those listed above.
Note On Fuzz Circuits: The diode-based fuzz circuit used in the last two preamps are based on article “Build The Mod Box” by Thomas Henry and Jack Orman, in the May 1997 Electronics Now magazine (p.45). Obtain the article free online with this link.
https://www.muzique.com/news/images2/Mod_Box_May_1997.pdf
It originally specified the TL074 quad op-amp since it had four sub-circuits, and was operated from a split-supply. And despite being somewhat dated (25 years old), the circuitry has remained valid to this day, though I have adapted the diode arrays to conform to a single-supply circuit.
Additional Notes: Most circuits here are based on designs in the book “Building Electric Guitars” by Martin Koch. [$33.56 on eBay.] But the input stage of the second preamp is instead based on a design by Craig Anderton appearing in the Nov. 1981 issue of Guitar Player magazine. [Original issues start at $10.00 on eBay.] Those exact circuits cannot be found online, so a link to them is not available. Yet, I have depicted them accurately but for the minor additions I mentioned at the beginning of this post. Furthermore, while I receive much help diagnosing the diagrams I posted at first, I supplemented that help with online research, and an electronics textbook used at an accredited university. Consequently, all diagrams above have been updated and should be viable, but I would still treat them as experimental until after breadboard testing efforts have been completed.
Final Note: For comparison, the diagrams originally posted have been retained in the Attachments folder at the bottom of this post, while the updated versions are also there. I am embarrassed by the original ones, but proud of the new ones, though members who helped me with them deserve lots of credit. One thing should be mentioned, however, regarding the 0.2uF capacitors going to ground on the second stages of most of the diagrams. That, along with its associated resistor, sets the low-frequency cutoff for the associated op-amp at 80 Hz for 6-string guitar. But for bass-guitar, and 7-string or 8-string guitar, make it 0.43uF, for a 40 Hz cutoff. And for no low cutoff at all, it can be omitted. And by the way, the following replies correspond to the original diagrams, not the new ones. So, if you want to know what they are talking about, refer to the old diagrams as left in the Attachments.
EOF
Here are six preamps for guitar using op-amps; each operated from a single 9V battery as the power supply, thus making them suitable for stomp-box applications. Sources for the diagrams are noted with the diagrams. The circuits are faithful to original diagrams but for minor changes, such as the adding of an input level control or the use of a pot in a negative feedback loop to provide the user with a gain control. However, while based on proven designs, these designs must still be considered experimental. Also, the diagrams originally posted had flaws, which were corrected according to advice from forum members here, who I thank for their help. The diagrams shown now are updated versions (but some may be updated again if needed).
The specified IC is the OPA2156 dual low-noise op-amp IC, but an original TI unit can be expensive and may take a long time for delivery. So, I have listed a number of pin-compatible substitutes at the end of this post, all of which will provide good results.
The next circuit features a Baxandall type of 2-band tone-control, followed by one with a Fender-style 2-band control, which works differently from the Baxandall-type, though both leave the mids fixed. For those who prefer three bands, all other circuits below involve 3-band Fender-style tone stacks.
Note the seemingly redundant Tone control at the output below. That is included to provide an additional means of shaping high-end response.
What follows next are the preamps with the 3-band tone-stacks having default Fender Bassman part-values.
Consider the difference in the way the input and output jacks are shown below. This would be a good way to do the foregoing circuits too, but I show this configuration only for the last two circuits. This one also has a fuzz circuit using diodes, providing clipping without having to overdrive op-amps. But if that is desired, an older dual JFET-input IC can be considered, having minimum supply voltage <= 4.5 V, such as the LF353.
The circuit below likewise has a diode-type fuzz circuit, but which is highly adjustable.
Here is the pinout diagram for a dual op-amp, along with pin-compatible example ICs.
ICs listed here should perform satisfactorily for the electric guitar and offer the least noise and distortion for circuits operated using a single 9V battery. They were chosen from among the best op-amps available today but whose minimum supply voltage is <= 4.5 VDC, since half of 9V is 4.5V, and a single-supply circuit sets the zero signal-reference operating-point midway between ground and the supply.
To get more distortion than the diodes provide, by overdriving a given circuit, use the LF353 instead of any of the ICs listed above. It is an older op-amp that will work with a single 9V battery as the supply and is a JFET-input op-amp, which means its overdriven tonality is preferred over that of most non-JFET-input op-amps. However, it will also work fine without being overdriven, and will not drain the battery nearly as fast as those listed above.
Note On Fuzz Circuits: The diode-based fuzz circuit used in the last two preamps are based on article “Build The Mod Box” by Thomas Henry and Jack Orman, in the May 1997 Electronics Now magazine (p.45). Obtain the article free online with this link.
https://www.muzique.com/news/images2/Mod_Box_May_1997.pdf
It originally specified the TL074 quad op-amp since it had four sub-circuits, and was operated from a split-supply. And despite being somewhat dated (25 years old), the circuitry has remained valid to this day, though I have adapted the diode arrays to conform to a single-supply circuit.
Additional Notes: Most circuits here are based on designs in the book “Building Electric Guitars” by Martin Koch. [$33.56 on eBay.] But the input stage of the second preamp is instead based on a design by Craig Anderton appearing in the Nov. 1981 issue of Guitar Player magazine. [Original issues start at $10.00 on eBay.] Those exact circuits cannot be found online, so a link to them is not available. Yet, I have depicted them accurately but for the minor additions I mentioned at the beginning of this post. Furthermore, while I receive much help diagnosing the diagrams I posted at first, I supplemented that help with online research, and an electronics textbook used at an accredited university. Consequently, all diagrams above have been updated and should be viable, but I would still treat them as experimental until after breadboard testing efforts have been completed.
Final Note: For comparison, the diagrams originally posted have been retained in the Attachments folder at the bottom of this post, while the updated versions are also there. I am embarrassed by the original ones, but proud of the new ones, though members who helped me with them deserve lots of credit. One thing should be mentioned, however, regarding the 0.2uF capacitors going to ground on the second stages of most of the diagrams. That, along with its associated resistor, sets the low-frequency cutoff for the associated op-amp at 80 Hz for 6-string guitar. But for bass-guitar, and 7-string or 8-string guitar, make it 0.43uF, for a 40 Hz cutoff. And for no low cutoff at all, it can be omitted. And by the way, the following replies correspond to the original diagrams, not the new ones. So, if you want to know what they are talking about, refer to the old diagrams as left in the Attachments.
EOF
Attachments
Revised Single-Battery Guitar Preamp Circuits
- Electronic Design
- 0 Replies
Verified Single-Battery Guitar-Preamp Designs
Here are six guitar preamp circuit designs, each shown powered by a single 9V battery. I posted some of them in this forum a while back but have lately revised them using a simulation website; CircuitLAB. www.circuitlab.com After working out all the bugs in a given diagram (very few thanks to help from my friends here at DIYAudio), the software at CircuitLAB displays a graph of circuit performance which verifies the design’s viability and allows for checking how changing part-values affect the circuit.
I have not built and tested these circuits. Thus, though verified, they must be viewed as experimental, so a prospective builder should breadboard test a chosen circuit before committing to a fully soldered build. But it is assumed that anyone contemplating using any of my designs as a basis for a new project is already an experienced technician. Hence, I cannot take responsibility for the outcome should someone base a project on any of my designs. I can only assure readers that they were verified using simulation software designed for that purpose. And I highly recommend CircuitLAB, if interested. They only allow one free trial project, but I like it so much I’m paying for it.
The diagrams involve various features and should be taken case-by-case to see which one or more may interest a possible builder. Also, it is allowed that subcircuits from one can be used in another or even used in a project not of my design. Notes are included in the diagrams to help make things clear and for specifying part numbers. First up is the most basic design, with Tone, Level, Bright, Drive, Gain, and Volume controls.
I have retained the symbols required by the CircuitLAB simulator for inputs and outputs, but a builder can simply imagine replacing them with female 1/4-inch phone-jacks, as shown below.
Inspiration for the input stage of the above preamp design must be credited to Austrian author Martin Koch, who wrote and self-published the book Building Electric Guitars, of which I have the 2nd Edition, 2001. The Circuits in question are on pages 49 and 60, but I made enough changes, compared to the originals, and as the output stage is of my own design, that I can claim the overall design as my invention. But in the interests of full disclosure, I have cited Koch as the source for the input stage.
Next is a design in which the input-stage was inspired by a Craig Anderton design appearing in a 1980s issue of Guitar Player magazine. Notice how he uses positive and negative feedback. The 2-band tone-control is an even older design, found in many op-amp applications circuits but which originated in the tube-amp days, specifically 1950. Called a Baxandall control, after its inventor, the first such circuit had a tube instead of an op-amp. For an online reference, see site https://tonestack.yuriturov.com, and select option Baxandall Active Dual Bass Cap. Combining the two circuits makes this diagram my creation, though I have just given full credit to whom it is due. [This is not a James tone-control, which uses much the same circuit but passively. Thus, the James control is often called a Passive Baxandall tone-control circuit.]
A little thinking reveals how the negative and positive feedback controls interact. The negative feedback pot is labeled “Overdrive” while the positive feedback pot is labeled “Gain”. And this makes sense because the Overdrive pot’s position, controlling negative feedback, makes the op-amp operate more cleanly when more feedback is applied, but otherwise allows the op-amp to approach its maximum output rating, causing distortion. This is why the arrow near the pot is in the opposite direction to the actual amount of negative feedback applied, so turning the pot clockwise makes the op-amp get louder. On the other hand, the Gain control sends feedback to the positive op-amp input, thus making it approach its maximum gain rating when more feedback is used, also causing distortion. Ordinarily, you don’t want positive feedback for an op-amp because of the danger of the device possibly exceeding its rated maximum-gain limit, which could in fact burn it out if unchecked. However, it's probably safe to assume that Anderton figured everything out before publishing the circuit, so the device will not exceed its rated maxima (with given part-values), even when overdriven.
Next up is a preamp circuit in which the input and output stages are completely of my own design, though obviously the tone-control is a 2-band Fender-style tone-stack, and inspiration for the diode-based fuzz circuit came from an old Electronics Now magazine article.
Specifically, see article “Build The Mod Box” by T. Henry and J. Orman appearing in the May 1997 issue, pages 45-49 and 60. Surprisingly, the article is available online. Here is the link. G:\Ebooks\ELECTRONICS\Magazines\Radio-Electronics\EN-1997-05.pdf
In the text of that article, and confirmed in other sources, germanium diodes and LEDs give better sounding fuzz than do silicone diodes. Also, an imbalance between the positive-going and negative-going diodes in an array introduces more even-order than odd-order harmonics into the fuzz tone. In the article, one diode was used in one leg of their array but two in the other. Here, I allow users to select between one, two, or three in different legs. However, only experimentation will reveal whether this arrangement will result in sounds pleasing to the ear. As an addendum in that respect, consider a well-written online source on diode distortion titled “Producing Asymmetrical Clipping”, linked here. https://www.muzique.com/lab/warp.htm
Below is a more elaborate version of the same kind of preamp, this with 3-band tone.
Note that I rely totally on Yuri Turov’s tone-stack calculator (cited above) when getting part-values for my tone-controls, instead of tediously crunching numbers like I used to do. In some cases, I use default values, as above, but in others I tailor the values to my personal preferences. For instance, I sometimes adjust them to increase the mids of the above tone-stack, as the default values (based on the original Fender design) have a tremendous dip in the mids when all the pots are at their middle positions. I also like to give it more treble and set the response graph as high in amplitude as it will go.
In the preamp design below, I use much the same op-amp circuits original to me but pair them with well-known classic distortion circuits that have been used in the past by many stomp-box makers and hobbyists. Craig Anderton was the first to discover that the inverting buffers in the CD4049 hex-inverting buffer IC produce an overdriven tone similar to that of a saturated preamp tube. Some online sources say his idea was first published in Guitar Player magazine but he had actually published it long beforehand in his book Electronic Projects for Musicians, from Amsco Publications (first copyrighted in 1975 but later copyrighted again in 1980, as far as my copy states, but I don’t know if there are later editions). In my copy, it’s the “Tube Sound Fuzz”, p 170 -173. Below are two identical clones my source says are used in MXR’s “Hot Tubes” pedal.
I was unable to confirm that MXR made a pedal called “Hot Tubes”, but I did find one by Electro Harmonix. See that circuit here. hottubes.gif (739×706) That stomp-box is itself quite dated, and is only available used, for instance, at www.guitarcenter.com. I have also noticed that many modern fuzz pedals use diode clipping instead of overdriven op-amps, or they are sticking with discrete transistor designs. However, whether the above circuit can compete in the tone department can only be known if the circuit is built and sound tests are performed for comparison. Yet, my design should sound very much like the old-school Electro Harmonix Hot Tubes pedal.
Finally for this post, the preamp circuit below features an octave circuit, though the source for it touts it as providing a distorted octave sound. Apparrently its octave tonality is pleasing to the ear. Here, I use a summing-amp to mix the direct and octave signals
Octave Circuit Source: David Morrin, at https://www.diystompboxes.com/smfforum/index.php?topic=186086
Note: You must sign up with DIY Stompboxes to access the original schematic, which was posted in their forum. However, I have rendered the circuit accurately between the Octave Drive and Octave Level controls, exclusive, while the Trim pot was in the original design, but I renamed it.
That site’s home page is linked here. https://www.diystompboxes.com
To replace the battery with a standard regulated power-supply, here’s an example circuit.
However, you can also use a 9V adaptor commonly used for stomp-boxes. Yet, here’s a tip for how to make the cheap ones work better (more like a regulated supply).
While the adaptor (wall-wart) is relatively inexpensive, a suitable choke is rather costly. However, if you can find a cheaper one that will work, that’s OK. What’s specified in the diagram are mere examples, provided for the reader’s convenience.
As reported by the designer in the noted Circuit Reference, this circuit will make an ordinarily noisy unregulated +9V wall-wart perform like a regulated supply. But on the other hand, Guitar Center has a 9V wall-wart they list as a “regulated” supply for stomp-boxes. [Probably Zener regulated, which is perfectly acceptable.] It’s only $19.99. The Live Wire PH17000 “Slimline” Power Supply, item # 1342450362499. https://www.guitarcenter.com
I make no apologies for using old circuits to create my designs. In my experience, if something works in electronics, it will continue to work as long as parts are available. And there is something to be said about the fact that many new commercial stomp-box circuits are based on old circuits or are reissues of old circuits. Proof of desirable tonality, however, will be known only should one of my designs get bult and is put to the test.
EOF
Here are six guitar preamp circuit designs, each shown powered by a single 9V battery. I posted some of them in this forum a while back but have lately revised them using a simulation website; CircuitLAB. www.circuitlab.com After working out all the bugs in a given diagram (very few thanks to help from my friends here at DIYAudio), the software at CircuitLAB displays a graph of circuit performance which verifies the design’s viability and allows for checking how changing part-values affect the circuit.
I have not built and tested these circuits. Thus, though verified, they must be viewed as experimental, so a prospective builder should breadboard test a chosen circuit before committing to a fully soldered build. But it is assumed that anyone contemplating using any of my designs as a basis for a new project is already an experienced technician. Hence, I cannot take responsibility for the outcome should someone base a project on any of my designs. I can only assure readers that they were verified using simulation software designed for that purpose. And I highly recommend CircuitLAB, if interested. They only allow one free trial project, but I like it so much I’m paying for it.
The diagrams involve various features and should be taken case-by-case to see which one or more may interest a possible builder. Also, it is allowed that subcircuits from one can be used in another or even used in a project not of my design. Notes are included in the diagrams to help make things clear and for specifying part numbers. First up is the most basic design, with Tone, Level, Bright, Drive, Gain, and Volume controls.
I have retained the symbols required by the CircuitLAB simulator for inputs and outputs, but a builder can simply imagine replacing them with female 1/4-inch phone-jacks, as shown below.
Inspiration for the input stage of the above preamp design must be credited to Austrian author Martin Koch, who wrote and self-published the book Building Electric Guitars, of which I have the 2nd Edition, 2001. The Circuits in question are on pages 49 and 60, but I made enough changes, compared to the originals, and as the output stage is of my own design, that I can claim the overall design as my invention. But in the interests of full disclosure, I have cited Koch as the source for the input stage.
Next is a design in which the input-stage was inspired by a Craig Anderton design appearing in a 1980s issue of Guitar Player magazine. Notice how he uses positive and negative feedback. The 2-band tone-control is an even older design, found in many op-amp applications circuits but which originated in the tube-amp days, specifically 1950. Called a Baxandall control, after its inventor, the first such circuit had a tube instead of an op-amp. For an online reference, see site https://tonestack.yuriturov.com, and select option Baxandall Active Dual Bass Cap. Combining the two circuits makes this diagram my creation, though I have just given full credit to whom it is due. [This is not a James tone-control, which uses much the same circuit but passively. Thus, the James control is often called a Passive Baxandall tone-control circuit.]
A little thinking reveals how the negative and positive feedback controls interact. The negative feedback pot is labeled “Overdrive” while the positive feedback pot is labeled “Gain”. And this makes sense because the Overdrive pot’s position, controlling negative feedback, makes the op-amp operate more cleanly when more feedback is applied, but otherwise allows the op-amp to approach its maximum output rating, causing distortion. This is why the arrow near the pot is in the opposite direction to the actual amount of negative feedback applied, so turning the pot clockwise makes the op-amp get louder. On the other hand, the Gain control sends feedback to the positive op-amp input, thus making it approach its maximum gain rating when more feedback is used, also causing distortion. Ordinarily, you don’t want positive feedback for an op-amp because of the danger of the device possibly exceeding its rated maximum-gain limit, which could in fact burn it out if unchecked. However, it's probably safe to assume that Anderton figured everything out before publishing the circuit, so the device will not exceed its rated maxima (with given part-values), even when overdriven.
Next up is a preamp circuit in which the input and output stages are completely of my own design, though obviously the tone-control is a 2-band Fender-style tone-stack, and inspiration for the diode-based fuzz circuit came from an old Electronics Now magazine article.
Specifically, see article “Build The Mod Box” by T. Henry and J. Orman appearing in the May 1997 issue, pages 45-49 and 60. Surprisingly, the article is available online. Here is the link. G:\Ebooks\ELECTRONICS\Magazines\Radio-Electronics\EN-1997-05.pdf
In the text of that article, and confirmed in other sources, germanium diodes and LEDs give better sounding fuzz than do silicone diodes. Also, an imbalance between the positive-going and negative-going diodes in an array introduces more even-order than odd-order harmonics into the fuzz tone. In the article, one diode was used in one leg of their array but two in the other. Here, I allow users to select between one, two, or three in different legs. However, only experimentation will reveal whether this arrangement will result in sounds pleasing to the ear. As an addendum in that respect, consider a well-written online source on diode distortion titled “Producing Asymmetrical Clipping”, linked here. https://www.muzique.com/lab/warp.htm
Below is a more elaborate version of the same kind of preamp, this with 3-band tone.
Note that I rely totally on Yuri Turov’s tone-stack calculator (cited above) when getting part-values for my tone-controls, instead of tediously crunching numbers like I used to do. In some cases, I use default values, as above, but in others I tailor the values to my personal preferences. For instance, I sometimes adjust them to increase the mids of the above tone-stack, as the default values (based on the original Fender design) have a tremendous dip in the mids when all the pots are at their middle positions. I also like to give it more treble and set the response graph as high in amplitude as it will go.
In the preamp design below, I use much the same op-amp circuits original to me but pair them with well-known classic distortion circuits that have been used in the past by many stomp-box makers and hobbyists. Craig Anderton was the first to discover that the inverting buffers in the CD4049 hex-inverting buffer IC produce an overdriven tone similar to that of a saturated preamp tube. Some online sources say his idea was first published in Guitar Player magazine but he had actually published it long beforehand in his book Electronic Projects for Musicians, from Amsco Publications (first copyrighted in 1975 but later copyrighted again in 1980, as far as my copy states, but I don’t know if there are later editions). In my copy, it’s the “Tube Sound Fuzz”, p 170 -173. Below are two identical clones my source says are used in MXR’s “Hot Tubes” pedal.
I was unable to confirm that MXR made a pedal called “Hot Tubes”, but I did find one by Electro Harmonix. See that circuit here. hottubes.gif (739×706) That stomp-box is itself quite dated, and is only available used, for instance, at www.guitarcenter.com. I have also noticed that many modern fuzz pedals use diode clipping instead of overdriven op-amps, or they are sticking with discrete transistor designs. However, whether the above circuit can compete in the tone department can only be known if the circuit is built and sound tests are performed for comparison. Yet, my design should sound very much like the old-school Electro Harmonix Hot Tubes pedal.
Finally for this post, the preamp circuit below features an octave circuit, though the source for it touts it as providing a distorted octave sound. Apparrently its octave tonality is pleasing to the ear. Here, I use a summing-amp to mix the direct and octave signals
Octave Circuit Source: David Morrin, at https://www.diystompboxes.com/smfforum/index.php?topic=186086
Note: You must sign up with DIY Stompboxes to access the original schematic, which was posted in their forum. However, I have rendered the circuit accurately between the Octave Drive and Octave Level controls, exclusive, while the Trim pot was in the original design, but I renamed it.
That site’s home page is linked here. https://www.diystompboxes.com
To replace the battery with a standard regulated power-supply, here’s an example circuit.
However, you can also use a 9V adaptor commonly used for stomp-boxes. Yet, here’s a tip for how to make the cheap ones work better (more like a regulated supply).
While the adaptor (wall-wart) is relatively inexpensive, a suitable choke is rather costly. However, if you can find a cheaper one that will work, that’s OK. What’s specified in the diagram are mere examples, provided for the reader’s convenience.
As reported by the designer in the noted Circuit Reference, this circuit will make an ordinarily noisy unregulated +9V wall-wart perform like a regulated supply. But on the other hand, Guitar Center has a 9V wall-wart they list as a “regulated” supply for stomp-boxes. [Probably Zener regulated, which is perfectly acceptable.] It’s only $19.99. The Live Wire PH17000 “Slimline” Power Supply, item # 1342450362499. https://www.guitarcenter.com
I make no apologies for using old circuits to create my designs. In my experience, if something works in electronics, it will continue to work as long as parts are available. And there is something to be said about the fact that many new commercial stomp-box circuits are based on old circuits or are reissues of old circuits. Proof of desirable tonality, however, will be known only should one of my designs get bult and is put to the test.
EOF
Tubes4HiFi SP14 really noisy!
- By perkri
- Tubes / Valves
- 254 Replies
Hi,
I ordered the kit without the chassis, as I wanted to build my own - plus I wanted to try to save some $$$’s
I’m getting a LOT of noise out of this…
All the voltages are as they should be.
B+ is 276vdc
H+/H- is 6.13 and 5.87
Voltage drops from 313 to 276 across D13 (both sides…)
6.43vac on heater from transformer
I have checked, double and triple checked the wires from all RCA inputs/outputs. The ground bus and all the connections to that, the ground to the circuit board from the bus. I’ve gone over the input selector, and all the wires coming and going from that. All the connections from the selector, through to the gain and volume controls. The output from the volume to the board, and ground wire are as outlined in the instructions.
I did not install the tape switch, and ran the wires straight from selector to the gain pots.
There are two things I changed as far as the power supply goes. I used an old school toggle switch in place of the power switch that came with the kit. And I accidentally reversed the red and black primaries to the transformers from a hot/neutral perspective. But I don’t think the transformers care about hot/neutral?
The noise is the same regardless of gain/volume settings. It’s the same in both channels. It gradually comes up in volume as the unit powers up. As soon as it’s powered off, it disappears but music keeps playing until it fades away.
The noise is the same, albeit with different volumes, if I run it into my DIY Hiraga Super 30 Class A SS amp, or my DIYAudio VFet SE SS amp.
Thank you for taking the time to read through this, any help would be greatly appreciated!
P
This is the noise as it presents at the speaker…
I ordered the kit without the chassis, as I wanted to build my own - plus I wanted to try to save some $$$’s
I’m getting a LOT of noise out of this…
All the voltages are as they should be.
B+ is 276vdc
H+/H- is 6.13 and 5.87
Voltage drops from 313 to 276 across D13 (both sides…)
6.43vac on heater from transformer
I have checked, double and triple checked the wires from all RCA inputs/outputs. The ground bus and all the connections to that, the ground to the circuit board from the bus. I’ve gone over the input selector, and all the wires coming and going from that. All the connections from the selector, through to the gain and volume controls. The output from the volume to the board, and ground wire are as outlined in the instructions.
I did not install the tape switch, and ran the wires straight from selector to the gain pots.
There are two things I changed as far as the power supply goes. I used an old school toggle switch in place of the power switch that came with the kit. And I accidentally reversed the red and black primaries to the transformers from a hot/neutral perspective. But I don’t think the transformers care about hot/neutral?
The noise is the same regardless of gain/volume settings. It’s the same in both channels. It gradually comes up in volume as the unit powers up. As soon as it’s powered off, it disappears but music keeps playing until it fades away.
The noise is the same, albeit with different volumes, if I run it into my DIY Hiraga Super 30 Class A SS amp, or my DIYAudio VFet SE SS amp.
Thank you for taking the time to read through this, any help would be greatly appreciated!
P
This is the noise as it presents at the speaker…
Anyone have the schematic for this Ebay 1541 DAC PCB?
- By kilohertz
- Digital Line Level
- 15 Replies
Hi guys,
Just received this PCB which I bought on a whim thinking it would be fun to experiment with, but now the seller is telling me he can't supply the schematic. Does anyone out there have the schematic for this very common 1541 DAC PCB? I have contacted multiple vendors of this with no reply.
Thank you.
Just received this PCB which I bought on a whim thinking it would be fun to experiment with, but now the seller is telling me he can't supply the schematic. Does anyone out there have the schematic for this very common 1541 DAC PCB? I have contacted multiple vendors of this with no reply.
Thank you.
Cheap printed circuit boards starting with 0,0375 Euro / cm2
- By msdesigner
- Vendor's Bazaar
- 521 Replies
Attachments
Drive NOS AD1865/62,PCM1704/02/63,TDA1541 from FIFO: Universal I2S-PCM driver board
- By iancanada
- Digital Line Level
- 1003 Replies
Attachments
Ultimate Open Baffle Gallery
From time to time I stumbled across really nice OB / Dipole designs. Usually I just put them in my favorites, but it may be really nice if we have an exhaustive list of OB systems out there.
Post your systems too! Pics and short description.
===
Let me start with this really nice implementation by Perfect8. No spouse frowning here 😀
http://www.perfect8.com
Post your systems too! Pics and short description.
===
Let me start with this really nice implementation by Perfect8. No spouse frowning here 😀
http://www.perfect8.com