I have a lot of wima mkp5 0.22uf capacitors left over from previous projects, I tend just to use those. I dont think the bypass cap value is critical, as long as its a lot lower than the cap your bypassing.
You are talking about the caps people add in parallel to larger value caps right?
Hello, I have some doubt about two groups of capacitors.
The yellow rectangle is between the volume knob and the opamps - is this audio signal path? Isn't it better to use there film caps?
Also for the green marked rectangle - these can be also replaced with film caps? And is this 10uF value the best for them?
I can try to fit polyester Epcos on both places if is OK to do that
The yellow rectangle is between the volume knob and the opamps - is this audio signal path? Isn't it better to use there film caps?
Also for the green marked rectangle - these can be also replaced with film caps? And is this 10uF value the best for them?
I can try to fit polyester Epcos on both places if is OK to do that
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I would change the big PSU caps and the 4 audio input caps first.
PSU caps: Nichicon FG or FW (neutral sound). Nichicon VZ & Elna Silmic II (warm sound). Nichicon PW (analytical sound).
Audio caps: Nichicon KZ, FG or FW (neutral). Elna Silmic II & Nichicon VZ (warm).
The KZ for instance sounds better than many film/foil caps so be careful with polys.
If you use Nichicon on the PSU you can make the sound warmer by adding small Silmic II or VZ in parallel.
A very important mod is to put a much larger cap to the AVDD rail (pin14), at least 220uF. This makes a HUGE difference. In comparison PFFB is rather unimportant.
PSU caps: Nichicon FG or FW (neutral sound). Nichicon VZ & Elna Silmic II (warm sound). Nichicon PW (analytical sound).
Audio caps: Nichicon KZ, FG or FW (neutral). Elna Silmic II & Nichicon VZ (warm).
The KZ for instance sounds better than many film/foil caps so be careful with polys.
If you use Nichicon on the PSU you can make the sound warmer by adding small Silmic II or VZ in parallel.
A very important mod is to put a much larger cap to the AVDD rail (pin14), at least 220uF. This makes a HUGE difference. In comparison PFFB is rather unimportant.
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Thank you for the info, I appreciate.
However from here https://www.ti.com/product/TPA3250 - I see pin14 is OSC-IOM
AVDD is specified pin9
Is the photo with the big 470uF cap between the DC decoupling caps and the heatsink yours? 🙂
I would like to know what is this mod delivering
Спасибо!
However from here https://www.ti.com/product/TPA3250 - I see pin14 is OSC-IOM
AVDD is specified pin9
Is the photo with the big 470uF cap between the DC decoupling caps and the heatsink yours? 🙂
I would like to know what is this mod delivering
Спасибо!
Regarding AVVD: I had to change my heatsink even after putting the cap horizontal on the PCB. My original cap was a dirty cheap SMD garbage (1uF or even smaller). Now I have a Panasonic Pureism PXL cap there with 470uF/16V. Much better bass & body. Much cleaner overall sound. Instruments sound more realistic. Less electronic haze in the upper mids, more transparency. In my setup this mod produced considerably better sound quality. I remember the moment when I've done this mod and was listening I thought: Now we are talking!
AVVD rail (brought out for decoupling at pin 14 (TPA-3255)).
AVVD rail (brought out for decoupling at pin 14 (TPA-3255)).
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THX for the pic
if i remember right Abrax wrote this at his modifications that he use a big cap at AVVD
chris
if i remember right Abrax wrote this at his modifications that he use a big cap at AVVD
chris
i wrote this in some pages before...page 56
About pin 9 and pin 14 AVVD
Watch out!!!
correct is pin 9 = AVVD. if you look at the datahseet the pin configuration layout is correct. the other diagram is wrong = AVVD pin 14 !!!
chris
About pin 9 and pin 14 AVVD
Watch out!!!
correct is pin 9 = AVVD. if you look at the datahseet the pin configuration layout is correct. the other diagram is wrong = AVVD pin 14 !!!
chris
Thank you chermann! I had the luck that I printed the right schematic before I modded the AVVD rail.
The pic in post #1092 is WRONG !!! DON'T USE IT !!!
AVVD decoupling pin:
TPA3250 - Pin09
TPA3255 - Pin14
The pic in post #1092 is WRONG !!! DON'T USE IT !!!
AVVD decoupling pin:
TPA3250 - Pin09
TPA3255 - Pin14
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I’ve got all of that to look forward to when I finally get home in February. I’ve got 2 to do, one for 8ohms and the other for 4ohms.