TPA3255 - all about DIY, Discussion, Design etc

Member
Joined 2019
Paid Member
Thanks Dr. so now i wait for my stuff to arrive. More then likely I will want to swap Opamps. Seems that is what others are doing. I’m researching now, but there appears to be a lot of options. My goal is a larger sound stage, any suggestion out there where I can start?

Rick D & mamocel: I just bought one of drMordor’s Class D amp with the PS built onto the PCB. It came stock with NE5532s. I’m a chronic op-amp roller, I admit. His amp sounded so good as it arrived I have no desire to change anything on it. It is just magical sounding as is...

Just my two cents.

Cheers, Pete
 
Dear friends,
I bought this amplifier:
TPA3255 2x260W 2Ch Class D Audio Amplifier|Amplifier| - AliExpress
And it's great.
I wanted to have more presence and I changed the OPA of there to a LM4562NA from Texas instrument's site.
Now it has more presence and it's nice but it lacks the delicate highs. (it seems that the sound is more condensed than before)
2 questions:
1. Which OPA is the best for this board?
2. What else can I change to improve the sound (but not too much complicated because I'm not professional like many of the people here).

Thank you very much!
 
This opa gets my vote, OPA1622 DIP8 High Current Output Low Distortion Dual Op Operational Amplifier | eBay This uses a virtual ground(0V) which works quite well but there is a mod to tie opa's ground directly to amp's ground. The mod is explained a few pages back in this thread but its really not necessary. I wouldn't call this opamp forward sounding but its topend is extremely precise. There's a reasion this opamp comes highly recommended on many forums.
 
Absolutely 0 issue with the OPA1656, nothing to report and running cold.
The OPA1656 is pretty expansive but still ok, you can find it here with gold SOIC > DIP8 adapter :

OPA1656 SoundPlus ™ ultra-faible bruit et la distorsion, Burr-Brown ™ Audio opamp | eBay

IMG-20200416-130839.jpg
 
Member
Joined 2019
Paid Member
Dear friends,
I bought this amplifier:
TPA3255 2x260W 2Ch Class D Audio Amplifier|Amplifier| - AliExpress
And it's great.
I wanted to have more presence and I changed the OPA of there to a LM4562NA from Texas instrument's site.
Now it has more presence and it's nice but it lacks the delicate highs. (it seems that the sound is more condensed than before)
2 questions:
1. Which OPA is the best for this board?
2. What else can I change to improve the sound (but not too much complicated because I'm not professional like many of the people here).

Thank you very much!

I’m with impuls60 about the 1622 in the 3eAudio amp. The caveat is my board came with Silmic II caps (which are colored more like cerafines) rather than bipolar UES green caps or the other polar Nichicon cap option. 1656 would not be a bad choice either but I just thought 1622s gave me a more airy presentation than 1656.

You can get the 1656 already mounted here SOIC-8 to DIP Adapter - BrownDog Adapters - 970601. They unfortunately do not have a mounted 1622 option. If you’re good with soldering you can just get the blank adapters and do it yourself.

Cheers, Pete
 
Dear friends, thank you all VERY MUCH!

The seller of the TPA3255 told me to try OPA1612 or OPA 1602.
Then I read this thread:
Test performance of AOP Burson/SPARKOS/SONIC994/1612, ..... | Page 3 | Audio Science Review (ASR) Forum

And I really don't know what to do.
There is an advice to try 1656 and the best is 1642.

For music with delicate, FULL and balanced sound which is better?
1612, 1622, 1602, 2064, 1656 or 1642?

Another question, which is the cheapest place to buy it but ready to put it on the socket?
Thank you!
 
Last edited:
I’m no where near an expert here but finding the exact perfect Opamp based on recommendations is near impossible. We all hear things differently, speaker design, room acoustics, as well as other components in your system can impact what you hear. I read that the brand of capacitors in your power supply can impact the bottom end. So you may just have to pick a few based on what is suggested across multiple forums and bite the bullet and try them.
 
Well folks, so as i had communicated, I found an Eyeboot 600w 48v power supply model AM-600-48S on amazon for $28 usa. It is a smaller version of their standard model. Was suppose to have the same specs and features. Well, the temp controlled fan is not there. Thermistor and transistor has been removed. Fan is hard wired on. So I’m trying to decide if I send it back and get a meanwell lrs- 350-48 or build a thermistor circuit to control the fan. Kind of hard to turn away the 600w. Also this supply has 2 Black KMH 250v 820 uf capacitors on the main bus. Is his enough? Are theses a good brand?
 
Member
Joined 2019
Paid Member
I’m no where near an expert here but finding the exact perfect Opamp based on recommendations is near impossible. We all hear things differently, speaker design, room acoustics, as well as other components in your system can impact what you hear. I read that the brand of capacitors in your power supply can impact the bottom end. So you may just have to pick a few based on what is suggested across multiple forums and bite the bullet and try them.

AMEN brother! Without a scope (I don’t own one) it’s all alchemy and one can only use one’s satisfaction/impression levels to judge.

Pete
 
Last edited:
I’m no where near an expert here but finding the exact perfect Opamp based on recommendations is near impossible. We all hear things differently, speaker design, room acoustics, as well as other components in your system can impact what you hear. I read that the brand of capacitors in your power supply can impact the bottom end. So you may just have to pick a few based on what is suggested across multiple forums and bite the bullet and try them.

That's why i'm using 3e audio fully balanced without Op amp (by-passed), full silver cable, a 36v lithium battery (very clean option) and an active room correction (convolution) :)
 
Dear friends, thank you all VERY MUCH!

The seller of the TPA3255 told me to try OPA1612 or OPA 1602.
Then I read this thread:
Test performance of AOP Burson/SPARKOS/SONIC994/1612, ..... | Page 3 | Audio Science Review (ASR) Forum

And I really don't know what to do.
There is an advice to try 1656 and the best is 1642.

For music with delicate, FULL and balanced sound which is better?
1612, 1622, 1602, 2064, 1656 or 1642?

Another question, which is the cheapest place to buy it but ready to put it on the socket?
Thank you!



Where are you based ? I have some 1656 chips mounted on adapters in the UK if you are interested. J
 
Dear friends, thank you all VERY MUCH!

The seller of the TPA3255 told me to try OPA1612 or OPA 1602.
Then I read this thread:
Test performance of AOP Burson/SPARKOS/SONIC994/1612, ..... | Page 3 | Audio Science Review (ASR) Forum

And I really don't know what to do.
There is an advice to try 1656 and the best is 1642.

For music with delicate, FULL and balanced sound which is better?
1612, 1622, 1602, 2064, 1656 or 1642?

Another question, which is the cheapest place to buy it but ready to put it on the socket?
Thank you!

I tested all those OP Amps with 3 different TPA325X by DrMordor boards.

My opinion :

OPA1642 > Great sound stage, the most colorful of the three.
Rather warm typed listening

OPA1602 > Very analytic, quite straightforward to listen to and less colorful than the 1642. Good soundstage as well

OPA1656 > The best, very holographic, ultra sharp and awesome soundstage, very equilibrated too

OPA1612 > best alternative to OPA1656, super soundstage,
a little less detailed in the restitution of the instruments but still analytic.