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TPA3255, TPA3251 with Post Filter Feedback(PFFB)

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Here's a block diagram of what I have. I tried powering the Arylic from a battery to try an avoid ground loop and it fixed the problem, so it's either a ground loop or a poor quality buck convertor - I suspect the latter. Will try some smoothing on the +5V to see if it fixes it. Thanks for your help.
 
But what you really want is a LT3045 based regulator. But you cant feed that 48V. And you can't set one after an USB block because it needs say 6V to work properly. If you have ambition with this setup you really ned to get a proper power supply for the streamer. But one can't hope for all that much with a complete receiver, controller and DAC for 49 bucks... 😉 The amp seems really good and in an other league than the Acrylic board. Maybe not the most balanced combo perhaps...

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i @
testing this week and will available end of March, will share massage here once ready for order.
@3eaudio, some class d amps seem to run out of steam when used for subs generating amplifying infasonic (down to 10Hz) how is the performace at this range, as I have not seem many charts. Is there a power drop? and if it is, how much is pex[-ected to drop (in percentage or watts) . Thanks
 
Got a pair of the monoblocks delivered. Nice things. I was an early adopter of the 3e stereo amp a good few years ago. Ended up selling it on whilst I played with other topologies. Eventually got back into a 3255 with the JLE amps and currently listen to Lester's Sylph200. I've built a few class A amps but I seem to return back to these!
I'm planning biamping and active XOs on my DIY 3 ways and the plan is these monoblocks on the LF and a 25 watt class A for the tops and mids( passive between these two).
Hopefully all in one chassis, so a channel amp all in one.
I currently use this Meishile PSU 48v 600w


https://a.aliexpress.com/_EzexYPl

with the Lester amp and so I bought another to power each monoblocks with one. They seem very quiet, though the speakers and from a PWM point of view, and also run very cool. I take the lid off and fan out.
 

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Got my monoblocks rigged up for testing. Using a opa551 buffer into a trafo for SE to balanced conversion. 'Meishle' 600 watt 48v smps per amp from AliX. Sounding good. Pretty quiet with ear up to soeaker. Slight hiss. My speakers definitely prefer some power up them. Don't seem to be getting too hot just sat on the wooden board but shall bind them down to the metal surface.
Will form the LF amp stage of an active biamp setup eventually but power the entire 3 way passive for now.
 

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I have tested both stereo and mono version (one Microaudio PSU) and find mono version better in all aspects...power, 3D stage, bass definition. After these test I decided to go mono way.
Hi Supernet,

That looks like the SMPS600-R2, am I right?
Where did you get the green board with the capacitors, and what is it for?

Could you share more details about your project parts, please?

I want to build something similar using the same 480-1-29A.

 
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