Not easy
Think it would require a servo to keep chips from fighting each other. Also a lot of testing to verify stability.
Almost there
Two remaining questions
Thanks!
Two remaining questions
- Because I thought it would look nice I put a flip switch on the front pannel. I'm noticing however that upon turning the amplifier off, I alway get a small shock. I can confirm that the button I grounded via the chasis. There are no shorts from the Live wire to ground. Does this mean this a discharge of static electricity? Rather annoying. Maybe it's best that I switch to a different type of on/off switch?
- The external LED is not powering on. I pressume the voltage is too low (1.7V). I pressume that I can change the value of R23 accomedate a higher voltage?
Thanks!
Attachments
The way to think about LEDs is current, not voltage. You will want about 2 mA through an LED for good illumination and long life. Select your resistor so that the source voltage - 1.7V gives the current you want.
You don't want to connect the 2 FE board power supplies together, so the LEDs should be on separate circuits. I have often just used one channel with an external LED as a power indicator and soldered the other channel LED to its on-board location.
On the other hand, I built a 4 channel where I brought all 4 LEDs to the front panel in a diamond pattern.
You don't want to connect the 2 FE board power supplies together, so the LEDs should be on separate circuits. I have often just used one channel with an external LED as a power indicator and soldered the other channel LED to its on-board location.
On the other hand, I built a 4 channel where I brought all 4 LEDs to the front panel in a diamond pattern.
As Jac already pointed out...no it isn't.
Just use one as front panel power indicator or bring both to the front panel.
Thanks. Fixed it. Put two different color LED's in parallel on a breadboard (3.3V DC). When blue are and red are put in parallel only the red one turns on. Removed the red led from the board and attached the external one. Added a resistor to dim the LED. Works great now.
Anyone an opinion regarding being shocked when turning off the Amp? I pressume it's static discharge, but won't to make sure that didn't overlook something ...
Anyone an opinion regarding being shocked when turning off the Amp? I pressume it's static discharge, but won't to make sure that didn't overlook something ...
Attachments
I saw in the previous pic that PGND is connected to the safety ground, it's not supposed to be, not directly, eventually you can use a ground loop breaker as per tutorial.
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Hi there! May I ask what box is that? I'd like to move to a smaller one, I'm running cabriolet but I have a pair of HiFi2000 SLIM LINE 02/350
that are way too big...Hi guys
I need your help. I build my-ref ampli in 2016. After a lot of tests with the oscilloscope (everything ok), I was unable to finish the job.
Last week I restart the the job and finished the connector cabling...
Yesterday I tryed my first run and one channel was OK.
The other channel unfortunatetly is not working. The led doesn't turn on and the relay doesn't switch.
This morning, following the signature on the PCB, I did some check with the multimeter and it seems that all is ok... at least for the signal part. +14V and -14V are ok and also +33V and -33V. Instead on C14 I have 33V and zero on the relay. So my idea is that something is wrong on the relay section, but I'm not able to understand what...
Can you help me?
I need your help. I build my-ref ampli in 2016. After a lot of tests with the oscilloscope (everything ok), I was unable to finish the job.
Last week I restart the the job and finished the connector cabling...
Yesterday I tryed my first run and one channel was OK.
The other channel unfortunatetly is not working. The led doesn't turn on and the relay doesn't switch.
This morning, following the signature on the PCB, I did some check with the multimeter and it seems that all is ok... at least for the signal part. +14V and -14V are ok and also +33V and -33V. Instead on C14 I have 33V and zero on the relay. So my idea is that something is wrong on the relay section, but I'm not able to understand what...
Can you help me?
Hi there! May I ask what box is that? I'd like to move to a smaller one, I'm running cabriolet but I have a pair of HiFi2000 SLIM LINE 02/350
Enclosure: Dissipante 02/300B 2U 4mm ARGENTO
Switch: 1 Pole 2 Positions Aviation Type Toggle Switch ON-OFF 250V 15A - Audiophonics
Led: LED Support + Blue LED - Audiophonics
Listening session: something seems off.
I just paired my amplifier with Monitor Audio Bronze 6 speakers (freshly purchased). I'm feeding the amplifier directly via my phone and some good quality music.
After listening to some track together with some friends we are bit underwelmed. Guitar tracks with gentle singing sounds spot on. So mids and highs sound very good. Classical music and other house/techno sound baffled, muddy.
I played around a bit with the EQ on my phone and made the next observation. When turning down the base tones to -10db, the mid and clarity jumps up. When bringing the base tones up againg to 0db, the mid tones lose all their clarity and sound very muddy.
I'ts hard to describe sound objectively, but me and my friend had exactly the same perception.
With my limited knowledge I'm thinking about
I have no ossciloscope or spectrum analyzer, so unfortunately I cannot objectify my perception.
I just paired my amplifier with Monitor Audio Bronze 6 speakers (freshly purchased). I'm feeding the amplifier directly via my phone and some good quality music.
After listening to some track together with some friends we are bit underwelmed. Guitar tracks with gentle singing sounds spot on. So mids and highs sound very good. Classical music and other house/techno sound baffled, muddy.
I played around a bit with the EQ on my phone and made the next observation. When turning down the base tones to -10db, the mid and clarity jumps up. When bringing the base tones up againg to 0db, the mid tones lose all their clarity and sound very muddy.
I'ts hard to describe sound objectively, but me and my friend had exactly the same perception.
With my limited knowledge I'm thinking about
- Maybe the speakers need some break in time
- Maybe the amp is not able to deliver enough power, to the Monitor Audio Bronze 6? I use two 225 VA transformers
I have no ossciloscope or spectrum analyzer, so unfortunately I cannot objectify my perception.
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Monitor Audio Bronze 6 should be a terrific match, I have Bronze 5 and they play very well together.
New speakers need some break in time and for sure the My_Ref FE too, at least 40-100 hours before bass stabilizes, at first is much more pronounced than it should, it's normal.
Also it seems you have the Nichicon in BOM in C9, as I've said here in the thread and in the build guide I don't like them that much for their sonic signature (they're still the best Mouser has to offer, though).
Those Nichicons also take a very long time to break in, expect 100 hours minimum.
No, I would say absolutely no... I fear you fried the LM3886 or the LM318.
Didn't you wrote me in PM that you had shorted outputs by the cabinet?
Yes, unfortunately I have 2 input and all output connected together
The strange thing is that only one channel was fried... was I lucky?
So do you think that I have to replace LM3886 or the LM318 or both?
Can I check something more?
Yes, unfortunately I have 2 input and all output connected together
The strange thing is that only one channel was fried... was I lucky?
So do you think that I have to replace LM3886 or the LM318 or both?
Can I check something more?
Check the 1 ohm resistor (R11 if I remembre correctly)
Thanks! Dissipante is really a nice case - 30cm depth is the right one, I really went too much far with 35cm.