Ideas/advice TPA3255 project

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Thanks for the nice comments everyone. It has over 50 hours of use now. The stepped resistor volume is great except for not having an open circuit at min volume so I can still hear something.

My 48v smps arrived! It took 10 minutes to swap over. It’s still 400w so I am not sure what the output of the amp actually is. My speakers can take it so I think 90-100w at 8ohms. I think the sound is now a tiny bit warmer, is that possible?

I just need some little rubber feet, some interesting wood for the front and possibly a power light. But for now I am just going to enjoy listening to lots of music.
 
I managed to keep the 24v 400w smps for £33. Then I went on eBay to buy a 10k DACT Type SMD Stepped Attenuator 21 step volume control. It is the one I had originally intended to use. Anyway one thing led to another and I bought a second one too and some speaker terminals, rca plugs, on/off switch and a 3eAUDIO TPA3251. I will look for a nice case and volume knob for this next project.
 
I might have Rick! I will post what I think of the new stepped attenuator when it gets here. The trouble I have now is my amp is too good, I can hear all the hissing in some of my older music, even remastered hi-res stuff. New music sounds a lot cleaner, so I need to expand what I listen to.
 
On my next TPA3255 "non public board" project, I will try this Digital Volume board :
It is really interesting because it includes a BVC input that allow you to add a Bluetooth controler later )

tinysine-tsa1020-module-controle-de-volume-numerique-selecteur-de-source.jpg

tinysine-tsa1020-module-controle-de-volume-numerique-selecteur-de-source.jpg
 
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On my next TPA3255 "non public board" project, I will try this Digital Volume board :
It is really interesting because it includes a BVC input that allow you to add a Bluetooth controler later )

tinysine-tsa1020-module-controle-de-volume-numerique-selecteur-de-source.jpg

tinysine-tsa1020-module-controle-de-volume-numerique-selecteur-de-source.jpg


Does this company have a Bluetooth board for this controller as I couldn’t see anything listed on their site. They also don’t say what chipset is used ?? They do have an IR based one listed. They do another model that already has the Bluetooth capability on the volume control board.

Given the amount of trouble you have gone to with rolling the Op Amps on the main board I always get worried about front ending your audiofile power amp with a cheap Chinese volume control. TI do a chipset for a volume control that some people seem to think is good enough to put in front of the TPA3255 series amplifiers.
 
Does this company have a Bluetooth board for this controller as I couldn’t see anything listed on their site. They also don’t say what chipset is used ?? They do have an IR based one listed. They do another model that already has the Bluetooth capability on the volume control board.

Given the amount of trouble you have gone to with rolling the Op Amps on the main board I always get worried about front ending your audiofile power amp with a cheap Chinese volume control. TI do a chipset for a volume control that some people seem to think is good enough to put in front of the TPA3255 series amplifiers.

I do not know so much about this volume control. It does not work like a regular potentiometer. It is a kind of digital volume control(chipset based) that needs a 12V DC to 35V DC PSU. But I own it =) You can also mute it when pressing into the center of the volume knob.
As soon as I get my non public TPA3255 Board from Zero Zone, I will give a try )
 
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I do not know so much about this volume control. It does not work like a regular potentiometer. It is a kind of digital volume control(chipset based) that needs a 12V DC to 35V DC PSU. But I own it =) You can also mute it when pressing into the center of the volume knob.
As soon as I get my non public TPA3255 Board from Zero Zone, I will give a try )

What’s the chipset on the board. Can you read it off the chips or send a photo ?
 
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Sure, the best I can do since it is really tiny...
If you zoom in, you would be able to check.

I see something like ATMEGA 328P UTH ....by ATMEL

ATmega328 - Wikipedia
Amazon.com: FlashTree 【2 Pcs】 ATMEGA328P-AU QFP ATMEGA328-AU TQFP ATMEGA328P MEGA328-AU SMD New: Home Audio & Theater

IMG-20200421-204821.jpg


So the little chip in the middle is a PT2257 digital volume control which is controlled by the Atmel custom programmed processor. Quite simple but not too sure how transparent the volume control will be. This company does other boards that already has the Bluetooth remote control functionality already built in so you can control it with an App on your mobile phone.
 

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So the little chip in the middle is a PT2257 digital volume control which is controlled by the Atmel custom programmed processor. Quite simple but not too sure how transparent the volume control will be. This company does other boards that already has the Bluetooth remote control functionality already built in so you can control it with an App on your mobile phone.

Wondom / Sure is making the same with a split board....
I read good opinions about it :

WONDOM AA-AB41116 PT2259 Module controle de volume numerique encodeur rotatif - Audiophonics

25820229397_394da2762b_b.jpg
 
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