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XRK RTR TPA3255 Reference class D Amp GB2

Founder of XSA-Labs
Joined 2012
Paid Member
Great to see only 8 more commitments before we can go to pre-orders and then production.

Btw, some of you are asking what PSU to use with this amp. That is all detailed in the GB1 thread. But here are the ones I have used successfully.

1. AliExpress 800w 48v SMPS for LED lighting. About $62 - need to disable the fan or replace with Noctua. At normal playing levels and even putting 125w per channel into 4ohms, the passive heatsink frame is enough to cool it.
KAYPW Switching Power Supply Light Transformer AC 110V 220V To DC 5V 12V 24V 48V Power Supply Source Adapter For Led Strip CCTV|Switching Power Supply| - AliExpress

2. AliExpress 1200w 12v to 48v DC-DC converter used with large lead acid UPS battery.
20A 1200W DC Boost Converter Step Up Power Supply 8 60V to 12 83V 24V 48V 12V Car Power Transformer Voltage Regulator Heat Sink|step up|step up 12vstep up to 12v - AliExpress

3. Connexelectronic SMPS800RE 800w 48v PSU.
SMPS800RE | Connex Electronic

Another idea is to look into SMPS from Cresnet. I hear they are also very well made. However, I have not tested them.

You will note that the SMPS are massively over sized to make sure they can overcome the start up inrush current. Smaller 300w SMPS will need a separate active slow start circuit to work and not worth it.

Most of these have an adjustment pot that lets you trim the output to a higher voltage as high as 51v typically.
 
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Vunce / 1 Amp / USA
xrk971 / 12 Amps / USA
StarDollar / 1 AMP / Norway
diy40 / 1 Amp / USA
Private message / 2 Amps / Brazil

telliottaus / 2 Amps / Australia
mb (mervin) / 1 Amp / Singapore
vizeta / 1 Amp / India
ahtllc / 2 amps / USA



mahtew / 2 Amp / Poland

CBRworm / 1 Amp / USA
 
Last edited:
Vunce / 1 Amp / USA
xrk971 / 12 Amps / USA
StarDollar / 1 AMP / Norway
diy40 / 1 Amp / USA
Private message / 2 Amps / Brazil

telliottaus / 2 Amps / Australia
mb (mervin) / 1 Amp / Singapore
ahtllc / 2 amps / USA
mahtew / 2 Amp / Poland
CBRworm / 1 Amp / USA

chermann/2 amps/ Austria


My apologies! I am withdrawing my name from the list due to some other commitments. I will try to participate in next round of GB.
 
I'm in for 1 more, with this and the adj-gain buffer, it'll make my DIY plans much easier.


Vunce / 1 Amp / USA
xrk971 / 12 Amps / USA
StarDollar / 1 AMP / Norway
diy40 / 1 Amp / USA
Private message / 2 Amps / Brazil

telliottaus / 2 Amps / Australia
mb (mervin) / 1 Amp / Singapore
ahtllc / 2 amps / USA
mahtew / 2 Amp / Poland
CBRworm / 1 Amp / USA

chermann/2 amps/ Austria


s610adam/ 1 amp / USA
 
Founder of XSA-Labs
Joined 2012
Paid Member
GB update, I have one more from Poland and Brazil backed out. So net loss of 1 or 3 more to go.

Vunce / 1 Amp / USA
xrk971 / 12 Amps / USA
StarDollar / 1 AMP / Norway
diy40 / 1 Amp / USA
*cancelled* Private message / -2 Amps / Brazil

telliottaus / 2 Amps / Australia
mb (mervin) / 1 Amp / Singapore
ahtllc / 2 amps / USA
mahtew / 2 Amp / Poland
CBRworm / 1 Amp / USA

chermann/2 amps/ Austria


s610adam/ 1 amp / USA

skamins/1 amp / Poland
 
We are so close now. Only 2 more to go! Of course, there is room for more if there is interest.

Thanks folks!

:cheers:

I just fitted the BTSB board to my amp from the first GB. Very happy with this, theres no hiss/hum/turn on noises whatsoever. Working really nice with an RME DAC and Jamo Concert 8.

Hopefully helpful for anyone trying to decide if to build one of these.
 

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