TPA3255 - all about DIY, Discussion, Design etc

There is a mono version of the board where the outputs are tied together. Check the ti data sheet to see how it's done properly. The mono version will give you 2x power in a 2 ohm load. The 3255 will be more reliable as the power demands will be spread across all 4 of the internal amplifiers instead of just 2 especially if you are using one 4 ohm woofer.
 
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Hi Guys:
There is a shortage of 10uH SER290 Coilcrafts at the moment. What are your thoughts on substituting a 15uH, 30A (same series SER2915H-153KL). The 10uH's are back ordered until mid-May of this year. It can be compensated with a smaller value of the filter film capacitor I think.

Datasheet here:
https://www.mouser.com/datasheet/2/597/ser2900-270685.pdf

I am going with the same series and 10uH, but 17A rating instead of the 28A rating. Should still work well as 17A was max current for 3255.
 
Just one question... Did you try the excellent TPA3251 board from AIYIMA.
This is the only board equiped with removable OP Amp. I own the 3E Audio and the AIYIMA TPA3255 also. The fact you can custom the OP Amp
opens up the possibilities of finding "your sound" Got some fantastic results with the AOP1622


3251.jpg

To directly answer this question, on the back of this thread I bought one of these Aiyima TPA3251 boxes (the A04), the OPA1622 (as recommended here) and the OPA2604 (as recommended by the seller) and the basic amp turned up today.
My first test listen was from my Plex server playing on my PC to a Samsung TV via HDMI with a Bluetooth connection to an Esinkin Bluetooth receiver connected to the amp with a headphone-to-rca cable.. using Mordaunt-Short Avant 902i bookshelf speakers. Perhaps not an audiophile route I know!

I've no idea how to write a review about how music sounds, but I have been completely blown away by a tiny silver box that cost not quite fifty quid, including the power supply, and that I'd almost forgotten I'd ordered a couple of weeks ago. The alternative op-amps haven't even arrived, and I just can't stop listening. Quite exceptional, irrespective of the price.
 
Oddly my channels were swapped as well..

That is my only complaint about this amplifier. I am not sure where the channels are cross-wired, but it can be easily remedied by switching the wires from the outputs on the PCB to the speaker binding posts for the left an right channels. I replaced the cheap wire with some short segments of Duelund DCA16GA Tin-plated Copper wire.

I also touched up as many of the solder joints in the signal path with the Cardas quad-eutectic Silver solder that I use in all my projects. I couldn’t touch up all the volume pot contacts. I would have had to remove the small PCB that the volume pot is soldered to, and I was just too lazy to do it.

I am pleased with the purchase enough to leave it alone until I receive the OPA1622 op amps to install into the amp.
 
Thanks Rich. Yes, separation and detail, they are suberb. I had a long listening session yesterday and got no fatigue, and rediscovered a lot of my music that had got lost in the convenience of Spotify streaming. I'm now looking in to a comparable DAC.
Cheers, Steve.

If you are looking for a comparable DAC / preamp. Take a look at my review of this AIYIMA Preamp. DAC ! Awesome !
Full Nichicon caps 4 AOP inside, remote control etc

[REVIEW] AIYIMA Tube Pream MC33078 / T5. Pictures inside

IMG-20200226-201516.jpg

IMG-20200226-202230.jpg
 
Hello,


To those working on the different "cheap" TPA3255 (or TPA3251), I would be interested to learn more about the heatksink arragement. There are many pictures from the top, but I have found none about the heatsink fixture:
- how is the bottom of the heatsink (fmlat ?)?
- thermal paste or not ?
- are there washer / spacer between the PCB and the heatsink ?
- other interesting aspects ?


Interested by pictures if you have some.



Best regards,

JMF
 
I have some pictures of my first TPA3255 non public Board by Zero Zone,

Maybe these pictures can help you about the Heatsink.
As far as I remember, I found some Thermal paste between the TPA3255 chip and the heatsink. Pretty like a computer CPU. No spacer between the Chip and the aluminium Heatsink.

PCB2.jpg

PCB1.jpg

PCB3.jpg


And another picture of the AIYIMA TPA3251 unmounted, as you can see there is a thin thermal paste layer between the chip and the Heatsink.

TPA3251.jpg
 
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Thansk Daniboun,
So, as you remember: flat bottom heatsink, thermal paste and basic fixing with screws and no spacer/washer.
Looks simple and OK. The "reference" heatsink is more complex, but won't fit my design (https://www.mouser.fr/datasheet/2/596/TS-TI1OP-1099-C1-R1-1620654.pdf) JMF


I want to say it is going to depend on your Board design... in any case, TPA32XX chips don't overheat. Never got any issue even with a very Powerfull PSU, tested with Linear and SMPS 48V / 500W, nothing to be worried about )

I have to admit that Custom 360DE heatsinks are really well made their TPA3255 board are absolutely fantastic :

IMG_9875_960.jpg
 
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If you are looking for a comparable DAC / preamp. Take a look at my review of this AIYIMA Preamp. DAC ! Awesome !
Full Nichicon caps 4 AOP inside, remote control etc

[REVIEW] AIYIMA Tube Pream MC33078 / T5. Pictures inside

Ah excellent, thank you! I've ordered one to see how it sounds :)

Keep in mind : Tubes and PSU are important parts for this DAC / Preamp. I recommend you to use a Leicke PSU 12V / 5A (German quality) that improves the performance. Concerning the Tubes, I got some really nice results with Sylvania and Tung Sol NOS tubes.
Be aware when changing the stock tubes, you need to be patient because they can't be removed so easily.
 
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Keep in mind : Tubes and PSU are important parts for this DAC / Preamp. I recommend you to use a Leicke PSU 12V / 5A (German quality) that improves the performance. Concerning the Tubes, I got some really nice results with Sylvania and Tung Sol NOS tubes.
Be aware when changing the stock tubes, you need to be patient because they can't be removed so easily.

Great advice, thank you :)
 
Hi guys
just finished two board on 3255
pffb
one with 450khz and pffb nominal s from national datasheet works fine
the second one 600khz 7uh inductors and 680nf c_out
the only difference is 600khz board didn't start with pffb
pffb on the boards differs only c_fb_out on 600khz board is 1nf instead of 220pf

both board planed to be used with 51v so R_fb_gnd 10k