ranshdow,
A lot of the TO92 NPN transistors will work. One thing to watch out for is the pin out so just make sure to place the part according to the pin label on the PCB rather than the part outline.
(For example, a BC547 can be used as long as you turn it around as compared to a ZTX450; the 2N4401 seems to have the same pinout as the ZTX450)
A lot of the TO92 NPN transistors will work. One thing to watch out for is the pin out so just make sure to place the part according to the pin label on the PCB rather than the part outline.
(For example, a BC547 can be used as long as you turn it around as compared to a ZTX450; the 2N4401 seems to have the same pinout as the ZTX450)
Hi,
While i'm waiting for boards to arrive im thinking what kind of Aleph 60 to build. I have heatsinks which are capable of dissipating around 220W per chanel and i would like to build the amplifier around them.
First option is to build Aleph 60 and then just raise the bias. The second is to raise the rail voltage to let say 38V for more power. Do i need to change any values in the schematic for 38V rails?
I already have 32 matched mosfets. Is there any advantage or disadvantage to use 16 instead of 12 mosfets per channel or only different junction temperature of the mosfets?
What is the proper way to add output mosfets. Just add fets, resistors and adjust the bias. Are the values of source resistors stays the same?
While i'm waiting for boards to arrive im thinking what kind of Aleph 60 to build. I have heatsinks which are capable of dissipating around 220W per chanel and i would like to build the amplifier around them.
First option is to build Aleph 60 and then just raise the bias. The second is to raise the rail voltage to let say 38V for more power. Do i need to change any values in the schematic for 38V rails?
I already have 32 matched mosfets. Is there any advantage or disadvantage to use 16 instead of 12 mosfets per channel or only different junction temperature of the mosfets?
What is the proper way to add output mosfets. Just add fets, resistors and adjust the bias. Are the values of source resistors stays the same?
Attachments
-just rummage through various ALeph schematics and find one with rails close to your intention; then study; Aleph is an Aleph is an Aleph - smallesst one is same as biggest one, "just" scale difference ... and here and there slightly different Aleph CCS gain ( amount of current contribution in sum output current)
-more mosfets - always trade off between final xconductance and input capacitance; you must decide for yourself where your curiosity is leading you, besides actual needs for current/power
- yup, when semi-scaling up - just add mosfets (and their gate/source resistors), adjust bias
-more mosfets - always trade off between final xconductance and input capacitance; you must decide for yourself where your curiosity is leading you, besides actual needs for current/power
- yup, when semi-scaling up - just add mosfets (and their gate/source resistors), adjust bias
See the Build Guide "Semiconductors" section about Q6-9 and Q10-13.
Q6-Q9
Must populate Q6 position.
Populate 2 of the 3 remaining positions on PCB and populate associated gate and source resistors.
Q10-Q13
Must populate Q10 position.
Populate 2 of the 3 remaining positions on PCB and populate associated gate and source resistors.
See my picture in post #36. This is set up for Aleph 30. These boards will replace my prototype boards in my monoblocks.
Q6 - to be populated (MUST BE POPULATED)
Q7 - not populated. Note that associated R29 and R37 are also not populated
Q8 - to be populated
Q9 - to be populated
Q10 - to be populated (MUST BE POPULATED)
Q11 - not populated. Note that associated R33 and R41 are also not populated
Q12 - to be populated
Q13 - to be populated
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Ok, then i will use my old power supply with 2x36.5V DC after loading. It seems close enough to original that no changes are required. Right?
With 3A bias i get 18W per mosfet if i use 12 of them and 14W if use 16 mosfets. So no problem with that.
I remember from some older posts that Nelson's favorite was Aleph 2, which use 12 output transistors and my curiosity goes in what direction go sound with different number of output mosfets.
As i read, all Alephs have great reviews.
With 3A bias i get 18W per mosfet if i use 12 of them and 14W if use 16 mosfets. So no problem with that.
I remember from some older posts that Nelson's favorite was Aleph 2, which use 12 output transistors and my curiosity goes in what direction go sound with different number of output mosfets.
As i read, all Alephs have great reviews.
Thanks for this list. Have prepared one and know how time consuming they can be. Just ordered and am starting to get parts for the kit sent by rhthatcher (Aleph J 30). Randy sends out the best stuff but charges WAY too little. Am leaning towards a monoblock build and have the PSU PCBs. Just need to decide on the Antek transformer size for each and get the chassis and parts. Thinking that a 200VA transformer should be sufficient for each mono as they are driving just one channel and Randy told me that the max draw was around 2 amps. Is this correct?
https://www.antekinc.com/as-2218-200va-18v-transformer/Thanks, folks. The DIYers are the best for sharing and helping.
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Working you through your decision making along with some "rules of thumb"...
First, you want to know if its 2A0 per channel or the total for a stereo amplifier, correct? Verify through Randy, the build guide, or here with the group. Also know your rail voltages. You also may have read some previous posts noting the expected total dissipation of the Aleph 30. Lastly, the build guide lists 300VA for a stereo PSU as a hint.
Rule of thumb for Class A - I'm good with a VA rating anywhere between 2x and 3x total dissipation with the Antek's I've used. Some go lower, and I've seen 1000VA transformers used on amps with ~150W dissipation. YMMV.
tl;dr - You should be more than fine with 200VA per channel.
Hope that helps toward a choice and some of the why...
First, you want to know if its 2A0 per channel or the total for a stereo amplifier, correct? Verify through Randy, the build guide, or here with the group. Also know your rail voltages. You also may have read some previous posts noting the expected total dissipation of the Aleph 30. Lastly, the build guide lists 300VA for a stereo PSU as a hint.
Rule of thumb for Class A - I'm good with a VA rating anywhere between 2x and 3x total dissipation with the Antek's I've used. Some go lower, and I've seen 1000VA transformers used on amps with ~150W dissipation. YMMV.
tl;dr - You should be more than fine with 200VA per channel.
Hope that helps toward a choice and some of the why...
IAIMH: You have helped me in the past and I thank you once again. Need to get the chassis ordered because of the wait time and am going to go with 2 deep mono blocks on Monday. Plenty of room for the long Aleph boards and plenty of dissipation for the mosfets (bunches of them on one of the heatsinks in each chassis):Working you through your decision making along with some "rules of thumb"...
First, you want to know if its 2A0 per channel or the total for a stereo amplifier, correct? Verify through Randy, the build guide, or here with the group. Also know your rail voltages. You also may have read some previous posts noting the expected total dissipation of the Aleph 30. Lastly, the build guide lists 300VA for a stereo PSU as a hint.
Rule of thumb for Class A - I'm good with a VA rating anywhere between 2x and 3x total dissipation with the Antek's I've used. Some go lower, and I've seen 1000VA transformers used on amps with ~150W dissipation. YMMV.
tl;dr - You should be more than fine with 200VA per channel.
Hope that helps toward a choice and some of the why...
https://diyaudiostore.com/products/mini-dissipante-3u?variant=12181188868With a 200VA Antek, Randy's PSU PCBs, and the rectifier and parts, think this will get the Aleph going. Have two M2xs with outboard PSUs (thanks, Paul in WA) and they sound dead quiet and super dynamic with 500VA Anteks (only ones available) and industrial-sized rectifiers. Like the mono or outboard approach.
FWIW I'm using a pair of AS-2218 in my F3 currently (a dual mono 0-48V PSU, not +/-24V) and thinking of repurposing the trafos and 4U/300 deluxe chassis for the Aleph 30. The latter would have to be set up as dual mono as I've read somewhere here that it's dangerous/problematic to try and run the secondaries of two different power transformers in series or in parallel, so I think the "new original F5" PSU would be out. Not sure I can fit two of the "V8 CRCRCs" inside a 4U/300 chassis though.
Honestly , I haven't read through the entire guide. I'll get to it.
Parts are on the boat. Hopefully a fast one.
Any time. Love to see more and more builds. I dig this stuff, and so many people have helped me.
Laughed at myself before I saw that you had linked to a selection with 2x chassis. I thought chassis prices had gone through the roof.
The mini's are fantastic. However... for this build, you're likely only going to use one heatsink per chassis, correct? You did the outboard PSUs for the M2x. You could... if you wanted... use the same PSUs for your M2x and your new Alephs to swap back and forth. You could also (perhaps with a bit of a wait) get the new monoblock chassis from Modushop. I don't know your other considerations, like if you need both amps running at the same time, or in different rooms. Just tossing out a thought. No matter what you choose, it'll be a great build.
No worries. Randy copied the relevant section for you in an earlier post. <Humming Carly Simon's, "Anticipation">
IAIMH writes:
"The mini's are fantastic. However... for this build, you're likely only going to use one heatsink per chassis, correct? You did the outboard PSUs for the M2x. You could... if you wanted... use the same PSUs for your M2x and your new Alephs to swap back and forth. You could also (perhaps with a bit of a wait) get the new monoblock chassis from Modushop. I don't know your other considerations, like if you need both amps running at the same time, or in different rooms. Just tossing out a thought. No matter what you choose, it'll be a great build."
Great ideas IAIMH.
However...
My pursuit is to make a variety of amps available along with multiple pres and media sources in order to select each for the best audio effect. As such, have built two Pass amps, two Pass/Wayne preamps, and designed and built multiple switching boxes to make this a realistic process. Here is one state of this madness:
Using these two boxes you can get a wide variety of audio combinations dialed in.
Want to hear what a vinyl source sounds like with a tube pre and 300B amp? Make the selections, turn on the amp, and away you go. Five seconds or so. BTW this is one incredible sound.
But let's say you want to massage the new Denafrips Ares 2 DAC with the Wayne WB2018 pre and try for some digital perfection through a pure Class A amp (the ACA). Takes 5 seconds. A cleaner sound is hard to imagine. This combination is my favorite morning sound to get you thinking straight.
My overall goal is to establish a lexicon of ideal audio combinations in the Medium/Preamp/Amp/Speaker chain. Then, I use the phrase "Active Amp Selection" to describe making these decisions in real time in order to improve your listening experience.
Yeah...it does work, can tell you.
Started one thread about the Dual Preamp and it was a colossal dud. Won't even try with the Active Amp Selection concept. Will have to wait for the second coming, I suppose.
Now in conversations with the DIY deity 6L6, discussed the pure class A option and he suggested the Aleph J as one of the best choices.
SO...HERE I AM. Ready to build another amp! And buy lots of new stuff! Oh how I hate buying lots of new things (LOL). Have to console myself with the realization that this is one of the ways to stay young.
Yeah...buying lots of stuff and staying young. For some of us, that's the way we are throwing away our retirement...
"The mini's are fantastic. However... for this build, you're likely only going to use one heatsink per chassis, correct? You did the outboard PSUs for the M2x. You could... if you wanted... use the same PSUs for your M2x and your new Alephs to swap back and forth. You could also (perhaps with a bit of a wait) get the new monoblock chassis from Modushop. I don't know your other considerations, like if you need both amps running at the same time, or in different rooms. Just tossing out a thought. No matter what you choose, it'll be a great build."
Great ideas IAIMH.
However...
My pursuit is to make a variety of amps available along with multiple pres and media sources in order to select each for the best audio effect. As such, have built two Pass amps, two Pass/Wayne preamps, and designed and built multiple switching boxes to make this a realistic process. Here is one state of this madness:
Using these two boxes you can get a wide variety of audio combinations dialed in.
Want to hear what a vinyl source sounds like with a tube pre and 300B amp? Make the selections, turn on the amp, and away you go. Five seconds or so. BTW this is one incredible sound.
But let's say you want to massage the new Denafrips Ares 2 DAC with the Wayne WB2018 pre and try for some digital perfection through a pure Class A amp (the ACA). Takes 5 seconds. A cleaner sound is hard to imagine. This combination is my favorite morning sound to get you thinking straight.
My overall goal is to establish a lexicon of ideal audio combinations in the Medium/Preamp/Amp/Speaker chain. Then, I use the phrase "Active Amp Selection" to describe making these decisions in real time in order to improve your listening experience.
Yeah...it does work, can tell you.
Started one thread about the Dual Preamp and it was a colossal dud. Won't even try with the Active Amp Selection concept. Will have to wait for the second coming, I suppose.
Now in conversations with the DIY deity 6L6, discussed the pure class A option and he suggested the Aleph J as one of the best choices.
SO...HERE I AM. Ready to build another amp! And buy lots of new stuff! Oh how I hate buying lots of new things (LOL). Have to console myself with the realization that this is one of the ways to stay young.
Yeah...buying lots of stuff and staying young. For some of us, that's the way we are throwing away our retirement...
That is fantastic!
I've often wanted something similar for A/Bing gear or just having a variety of gear more easily accessible for my listening "moods". I will definitely need to pick your brain a bit. I'd love to be able to add my 300B amps into the chain with the F4s or take them out... or do them in combinations. Even though it's talked about often by others, I still haven't done it. Having gear sitting 'unused' is a sad state, and I'm often lazy when it comes to hauling over another piece of gear or getting behind the rack to hook things up.
No thread's a 'dud', I'll have to check it out.
Agreed! The M2x was my 'first', and I absolutely adore it for its versatility (and sonics with a few of the IPSs), but there is something very special about an Aleph. It may have been 6L6 that mentioned something to me along the lines of "Everyone needs an Aleph".
Well, we can't take it with us. I'm working on disproving the 'old dog, new tricks postulate'. I think I have play dead and roll over down pat.
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See the Build Doc. What you're looking for is in the Trimpots & Adjustments section and the comments column in the BOM.
For Aleph 30