my boards are 1.72. I assembled everything but I only get very low sound from the speakers. Very low!
I checked voltages as indicated on the boards and they seemed all ok with the exception of the the voltage across R101/201 where I have 0.95 volts in stead of 1.25.
Thank you in advance for any help/suggestion.
I checked voltages as indicated on the boards and they seemed all ok with the exception of the the voltage across R101/201 where I have 0.95 volts in stead of 1.25.
Thank you in advance for any help/suggestion.
This is absolutely not normal...that voltage is set directly from the LM317, something gone really wrong.
Please post macro pictures of your boards.
Hi there! I'm planning to upgrade the PSU caps with a pair of Supertech 2T Slit Foil.
A good idea that will fit? Those are a bit bigger, 35mm diameter.
A good idea that will fit? Those are a bit bigger, 35mm diameter.
are you replacing the MAL225658103E3 caps with the supertech slit foil caps ? 35 mm diameter for both.
Sorry guys, me again! 😀 Too hot for soldering, so... I'm doing everything else.
I'm wondering about putting a vertical heatsink, insted of bolting the LM on case side.
What do you think? Could you suggest me a heatsink size?
Thanks again!
I'm wondering about putting a vertical heatsink, insted of bolting the LM on case side.
What do you think? Could you suggest me a heatsink size?
Thanks again!
-Question, can LM317T be replaced with LM317T/LF01?
-If no can it be replaced with LM317T from STMicroelectronics?
https://www.digikey.fi/en/products/detail/stmicroelectronics/LM317T/591677
Component shortage, even alternative LM317T/NOPB is out of stock from mouser..
-If no can it be replaced with LM317T from STMicroelectronics?
https://www.digikey.fi/en/products/detail/stmicroelectronics/LM317T/591677
Component shortage, even alternative LM317T/NOPB is out of stock from mouser..
I actually ordered LM317AT from texas instruments, which seemed to have same spec to my amateur knowledge, if it is completely wrong.. well ill order again i guess.
Any LM317 will work but the Onsemi ones are lower noise and better sounding.
Hello there, I finished to populate my boards and modified a little bit my disipante 3U case to mount properly the LM3886, but I have to many questions to go forward, the first one to complete the board is I would like to know if this the correct position for this capacitor and also for the zfoil but I think for the resistor is too late saw a picture in the build guide and followed them.Also for the hook wire is the mogami 2944 still the recommended one.
Attachments
Looks like this post are halt but need some help from Dario or anyone (I know EE are very busy, sorry to bother you guys) but in the previous post I was asking if that was the correct way to solder that capacitor, that is the last part to light my amp and for the money and time invested in it want to do it the right way again I understand it is cumbersome for you to help a person like me with limited electronics knowledge.Thanks in advance
Sadly I can't help with CMR's direction since they're not labelled accordingly, luckily they don't differ much so you can mount any way you want.
But if you want to take advantage of the best direction (and there is a difference) you can mount them using 2.5mm fastons and find the best direction for each channel by ear.
Faston Tab (571-1742428-1)
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Hi there! I'm ordering the "refined" parts from HiFiCollective this WE (damned Customs fees...)
So, I stil have a pair of the Mundorfs MCAP Supreme we used in old PCBs (C13), now ClarityCaps CMR: do you think it's worth putting them?
What about the SuperTech 2T for C101/201 ?
So, I stil have a pair of the Mundorfs MCAP Supreme we used in old PCBs (C13), now ClarityCaps CMR: do you think it's worth putting them?
What about the SuperTech 2T for C101/201 ?
IMHO, after the several builds I've done on this amp, I doubt you'll hear any difference with regard to orientation of this CMR cap. The MR variation of the ClarityCap didn't have an inside/outside foil formation but I can't find info on the CMR variation. I think you make a bigger impact on how this amp sounds by what you mount at C9 if sticking with the LM318 opamp. Nothing else I've built even comes close to the sound from this rework of the original Mauro's My_Ref especially since you've used the audiophile parts.
Cheers,
Pete
No, I tried to get rid of them for years, an amp with the more recent suggestions will sound much more natural and relaxed.
Never tried them so I don't have any clue.
So I'm going through my build, I have fitted OP828s as I don't have a preamp. I've gone and got 150pF Amtrans AMCH instead of 68pF recommended for C32. My EE skills aren't up to understanding that bit of the circuit. What would be the effect of fitting the 150pF instead of the 68pF?
OPA828 will be not stable with 150pF, if you want to keep those Amtrans you should change the opamp to ADA4627, according what @Joseph K wrote.
Yes, as Dario had pointed out, the cicuit will not work with OPA828 and C32 150pF.
either change that cap to 68pF-75pF (two pieces of 150pF in series)
Or just try to cut that trace between C12 (220pF input cap) and the -Inp of the opamp (Pin2 of the OPA828)
place there a cca 1kohm resistance in series, as it is shown in the attach.
Now the original 150pF cap can be kept, it should work (don't forget about the 5pF direct compensation cap between that same pin2 and pin6 of the OPA828)
And the elimination of the original compensation elements etc.
either change that cap to 68pF-75pF (two pieces of 150pF in series)
Or just try to cut that trace between C12 (220pF input cap) and the -Inp of the opamp (Pin2 of the OPA828)
place there a cca 1kohm resistance in series, as it is shown in the attach.
Now the original 150pF cap can be kept, it should work (don't forget about the 5pF direct compensation cap between that same pin2 and pin6 of the OPA828)
And the elimination of the original compensation elements etc.
attention, the above sketch is just for illustration showing the place where to insert that extra resistance. Would like to underline again, all the rest of modifications are valid & necessary, as before (in the case of applying that specific opamp)