does anyone own this board?
1Pcs Tpa3255 Vier Kanal High Power Digital Class D Verstarker Bord|Verstarker| - AliExpress
is it dual chip btl or 4ch single ended.
1Pcs Tpa3255 Vier Kanal High Power Digital Class D Verstarker Bord|Verstarker| - AliExpress
is it dual chip btl or 4ch single ended.
Claredes,have you tried bypassing the tubes? I actually prefer my board directly run'd balanced from a very hot dac signal. So the onboard opamps are not in use. The SNR is almost certain ruined with the tube circuitry. The 3255 scales superbly with a good dac. The 3255 haven't got any harshness to it so I feel it doesn't need tubes to melow it out.
Hello my friend!
I did not turn on the TPA3255 without the preamp.
I already configured it that way.
I have no signal source with balanced output, only RCA.
But your information made me curious about the performance of the TPA3255 running without a preamp.
Although I really liked the final result of the current configuration.
I think I'm going to do some tests.
Thank you very much for the suggestion!
The only thing that has worried me is the heating in the amplifier's heat sink and output inductors.
I have a 44VDC power supply and 5ohms speakers and the heat sink is getting really hot. Even though the fail or OTW leds do not light up.
I don't feel good about electronics heating up too much. Especially when they are Class D that do not usually heat up so much.
Last edited:
I removed the stock heatsink on my tpa3255 and replaced it with a 10mm thick aluminium L bracket sinking the heat into the heatfins on the cabinet. I also put a thermal pad between L bracket and cabinet so there is no extra ground loop between chip and cabinet. On the chip I used cpu thermalpaste for optimal heat transfer. This solution works really well! A simpler solution would be to use a 11-12db fan on top for cooling the whole board.
Good luck experimenting further with your amp! Its a very rewarding amp for diy experiments
Good luck experimenting further with your amp! Its a very rewarding amp for diy experiments
I removed the stock heatsink on my tpa3255 and replaced it with a 10mm thick aluminium L bracket sinking the heat into the heatfins on the cabinet. I also put a thermal pad between L bracket and cabinet so there is no extra ground loop between chip and cabinet. On the chip I used cpu thermalpaste for optimal heat transfer. This solution works really well! A simpler solution would be to use a 11-12db fan on top for cooling the whole board.
Good luck experimenting further with your amp! Its a very rewarding amp for diy experiments
Is your amplifier the 3e Audio?
If so, can you tell me if it comes with thermal paste between the TPA3255 and the heatsink?
Incredibly, I turned on my amplifier now to listen to music and the preamp is humming.
I will remove this preamp.
Do you know if a signal source with 700mV is able to excite the TPA3255 from 3e Audio?
Last edited:
Yes.
That was confirmed by the customer service of AIYIMA electronics.
I recieved the mail last night.
If I buy this switch 48v version, will it capable of withstanding the ampere flowing thru it?
16mm red blue yellow green white Light Hot Car Auto Metal LED Power Push Button Switch Self locking Type On off 5V 12V 24V 220V|on-off switch|on-off push buttonon-off button - AliExpress
Thanks for the feedback. I have purchased LLC type SMPS from aliexpress (Single 48V).
GHXAMP HIFI Switch Power Supply Dual DC 24V 48V 60V 80V 300 500W Power Supply Board With Heat Sink For Low power Amplifier 1pc|Amplifier| - AliExpress
Will the cap bank setup work with this PS also?
kindly advise
Last edited:
I removed the stock heatsink on my tpa3255 and replaced it with a 10mm thick aluminium L bracket sinking the heat into the heatfins on the cabinet. I also put a thermal pad between L bracket and cabinet so there is no extra ground loop between chip and cabinet. On the chip I used cpu thermalpaste for optimal heat transfer. This solution works really well! A simpler solution would be to use a 11-12db fan on top for cooling the whole board.
Good luck experimenting further with your amp! Its a very rewarding amp for diy experiments
Hello my friend!
I did the test today by connecting the 3e Audio directly to my signal source, without using the tube preamp.
What can I say...
It is quite another amplifier.
I immediately removed the preamp that was interfering negatively in the sound, in addition to having started humming.
In order not to lose the function of the display that I created for the valves on the panel, I placed a LED VU meter.
I also replaced the power transformer with a 26 - 0 - 26 and now I have approximately 36VDC and the 3e Audio board no longer heats the heatsink as before. Only if I use the volume too high, which I rarely do.
Thank you very much for the guidance of testing the TPA3255 without a preamp, really, it doesn't have to. His sonority is already very good, including the input sensitivity.
Attachments
Saran008: this might be of interest for you if you want to use those illuminated, lower voltage, circular switches. It adds on a soft-start circuitry however.
PCB: low voltage On-Off switch drives AC mains relay \ includes soft start .. H9KPXG
Regards, Pete
Hello,
did you have any chance to compare OPA2192 to OPA2189 or OPA2209?
Thank you very much
Rgds,
Martin
Thanks Doc, for the Advice. I think I buy 220V model switch from the same link and use on AC mains itself. (second switch in addition to the one along with IEC socket). will it be fine? thanks
Thanks Pete.. nice info, as i already purchased the case, no place for this. but definitely will have it in mind for future project.
Thanks for the clarification, when i start will go without cap bank first and see the available space and plan accordingly, whether to go for single large cap or a few caps in parallel.
Last edited:
I have a some questions about Op-Amps, my 3eAUDIO amp and DAC.
1) Does my 3eAUDIO TPA have 4 Op-Amps?
2) My Khadas Tone Board has Op-Amps so could I bypass the ones on my amp?
3) I read somewhere to bypass the Op-Amps you need to remove the 8th leg (not sure where I read this), could it be bent out of the way instead?
4) Can I fit any Din8 Op-Amp to my amp or do they have power ratings?
1) Does my 3eAUDIO TPA have 4 Op-Amps?
2) My Khadas Tone Board has Op-Amps so could I bypass the ones on my amp?
3) I read somewhere to bypass the Op-Amps you need to remove the 8th leg (not sure where I read this), could it be bent out of the way instead?
4) Can I fit any Din8 Op-Amp to my amp or do they have power ratings?
1. Not exactly, the amp has 2x dual-channel opamps.
2. the amps's onboard opamps perform SE-differential conversion, so you can only bypass them if your DAC (or any other source device) has differential outputs. Your Khadas Tone Board has single ended output, so no.
3. Yes. Of course we're talking about the older model 3e-audio amps with surface mount opamps.
4. You should read the recommendations about opamps throughout this forum thread. Current flavour-of-the-month seems to be the OPA1656 ...
but if your amp has surface mount opamps, it's going to require some precise soldering to do the swap.
2. the amps's onboard opamps perform SE-differential conversion, so you can only bypass them if your DAC (or any other source device) has differential outputs. Your Khadas Tone Board has single ended output, so no.
3. Yes. Of course we're talking about the older model 3e-audio amps with surface mount opamps.
4. You should read the recommendations about opamps throughout this forum thread. Current flavour-of-the-month seems to be the OPA1656 ...
but if your amp has surface mount opamps, it's going to require some precise soldering to do the swap.