TPA3255 Reference Design Class D Amp with PFFB

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I wanted this to be one of the first products I highlight in my new forum. This amp started as a GB in this thread.

TPA3255 Reference Design Class D Amp GB

There was a second GB here:

XRK RTR TPA3255 Reference class D Amp GB2

What can I say, this is a superb sounding amp. Quiet, powerful, dynamic, non fatiguing, low distortion.

JPS64 created a masterpiece with his signature symmetry, via stitched ground planes, and ultra short high current traces. The board is 2mm thick, 2oz copper, ENIG finish. Assembled in California using premium genuine Mouser-sourced BOM. Each amp is individually tested on an Audio Precision test stand at the factory and then sound quality tested by myself before shipping.

Many people have assembled this amp into a nice chassis and everyone loves the sound. With the right PSU, the amp has the distinction of being the quietest amp I have built. You cannot tell it is on with ear pressed to the speaker cone. Just silence.

I hope folks will share their builds here. Or feel free to ask technical questions.

Redjr made on of the nicest implementations. More here.

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Vunce made an awesome build with a linear PSU with an LT4320 Ideal bridge rectifier amp on a plank here:
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For best results, this amp should be paired with the BTSB balanced buffer which provides selectable gains (0dB/6dB/14dB/20dB) SE or Bal input and SE and Bal output. Since the TPA3255 with PFFB only has 15dB gain, it needs a preamp with about 14dB of gain in order to play music to its maximum levels. The BTSB is a superb preamp design by Jhofland. It started as a GB in this thread. Here is the panel mount version of the BTSB:
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Those of you who know me, know that I hate casework (chassis building). This most of my amps are “plank” amps. Amps on a plank of wood. Only the most special and deserving of amps get a chassis. Well this amp is one of those amps. More to come...
 

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Hi Folks,
Just wanted to let everyone know about an exciting collaboration between XRKAudio and Living Sounds Audio. LSA will be producing a commercial amplifier with the RTR TPA3255 as the OEM core along with the BTSB Panel Mount input buffer. All of this will be in a nicely made custom CNC’d aluminum chassis. All genuine Mouser BOM and premium components like Viborg binding posts.

Here are some renders and an initial prototype of the production line unit.

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We still need to tidy up the internal wiring - but it’s getting there:
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Hey thanks, guys. Some more progress photos. You can see this is not vapor ware anymore. These are not the correct binding posts. I spec’d premium solid copper with anodized aluminum knobs like in the renders. But wiring is a bit neater and buttons, switches and LEDs are connected.

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Some neat details like dual 18ga silicone RC race car wires for the speaker outputs for extra low impedance. Also silicone wire is used for power from SMPS to the amp.

The BTSB buffer is the best there is and provides auto switching detection of RCA or XLR with XLR being dominant.
 

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What a nice amp. I have been reading some reviews in the mean time and it seems to be a stunning piece. I have contacted Walter @ Underwoodhifi to see if he can ship one to The Netherlands as I am keen on comparing it to my Purifi EVAL1. Did you by any chance compare your design with the Purifi EVAL1?

BR,
Richard