Be easy on me Im relatively new to this DIY amp but do have experince with electronics and refurbing/fixing vintage amps etc as well as career in Electro Mechanical field. So I Finished this build using a 30 dollar ebay TPA3255 and it sounds excellent, just added an Alps 27 Potentiometer, for a power supply i have an external 48v 7amp used in Networking and telecommunications, its a low ripple low noise supply by ICT comm series. I have a dc jack mounted to back of case wich then runs to switch up front. I added a 4uf cap across the reset Mute which stopped the pop sound turning on and off per posts I saw here suggesting it.I have that seperate as It wouldnt fit in this case easily and this case has been chewed up inside over the last few projects. Ive since aquired better tools to do this stuff the right way going forward like better drill and bits as well as Dremel and few other doo dabs to aid in fabrication. The Alps pot shaft was quitelong so trimmed that down to fit the vol knob on (Yes I deburred and filed it beofre installing case. All and All Im quite pleased with this and am loving the latest Class D offerings, however Im wondering if Id actually see a sound improvement with one of these more expensive TPA BOARDS like the 3e and few others to justify the price? I also built a icepower amp using the 50asx and am waiting on wiring harness and am bulding one using the 125asx2 board so Ive been a class D busy boy lately. Pics of my system for attention. Any feedback always appreciated. TY guys Ive learned a lot lurking here.
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Thanks for posting. I am nearing the finish of my first class D, using the exact same board as you have so I have no experience of other TPA3255 boards...yet. I have some finishing decisions and touches to do re the mains power switch and whether I want a volume pot or not. Other than that, it sounds superb with an equally inexpensive 36v ebay SMPS.
I have a couple of questions...
How do you find the heatsink and output inductor temperatures when running at 48v, at idle or under load? Mine are warm to the touch, however at times they have heated up more, and I'm considering some ventilation as currently it is in a completely closed box.
I hadn't seen the 4uF cap mod across the reset/mute pads before. Does this make a big difference for you? I only get a very slight click through the speakers when powering on, and absolutely nothing when powering off.
One mod I have seen for these is swapping the standard opamps for something more exotic. Not done it myself, but some swear by it. Others reckon it makes no difference.
I have a couple of questions...
How do you find the heatsink and output inductor temperatures when running at 48v, at idle or under load? Mine are warm to the touch, however at times they have heated up more, and I'm considering some ventilation as currently it is in a completely closed box.
I hadn't seen the 4uF cap mod across the reset/mute pads before. Does this make a big difference for you? I only get a very slight click through the speakers when powering on, and absolutely nothing when powering off.
One mod I have seen for these is swapping the standard opamps for something more exotic. Not done it myself, but some swear by it. Others reckon it makes no difference.
This looks like (or is) the Shui Yuan board which has its own diyaudio thread.
In response to your question about whether the more expensive TPA3255 boards are worth it, I'd say yes, but it's up to you TBH.
Usually, you get what you pay for, but in a world of mass production it is less so.
For these Chinese products, they tend to stick to what the manufacturer recommends for PCB layout (straight up copy the EVM's) and parts, which will get them to output about 80% of the TPA's capabilities. However, there're no guarantees they won't subsitute some parts, like output filters, input caps, heatsinks, op-amps with inadequate or outright fake parts. The consequences can be unpredictable (burned amp or sound not as great as the TPA chip should be).
Expensive boards (like JlesterP's products) on the other hand, they spend more efforts on getting that last 20%, or even go above and beyond, in designing the layout, part choices...you can see for yourself in the link I gave you. If you have advanced, in-depth questions about how the amp works they may be able to answer you too, as they develop it themselves and have the schematics on hand.
In response to your question about whether the more expensive TPA3255 boards are worth it, I'd say yes, but it's up to you TBH.
Usually, you get what you pay for, but in a world of mass production it is less so.
For these Chinese products, they tend to stick to what the manufacturer recommends for PCB layout (straight up copy the EVM's) and parts, which will get them to output about 80% of the TPA's capabilities. However, there're no guarantees they won't subsitute some parts, like output filters, input caps, heatsinks, op-amps with inadequate or outright fake parts. The consequences can be unpredictable (burned amp or sound not as great as the TPA chip should be).
Expensive boards (like JlesterP's products) on the other hand, they spend more efforts on getting that last 20%, or even go above and beyond, in designing the layout, part choices...you can see for yourself in the link I gave you. If you have advanced, in-depth questions about how the amp works they may be able to answer you too, as they develop it themselves and have the schematics on hand.
What karlsonate said...
I have settled on the same board and have two of them now. I tried the "new improved" model, but struggled to find any improvement over the "primo gold capacitor" board. It might put out a couple of more watts when being fed sine waves into a dummy load, but in reality with music, I imagine the only difference would be survival during torture. Bigger heat sink, bigger output inductors translate to more heat leaving faster. As far as musical character and raw sound quality, I couldn't tell a difference.
I have settled on the same board and have two of them now. I tried the "new improved" model, but struggled to find any improvement over the "primo gold capacitor" board. It might put out a couple of more watts when being fed sine waves into a dummy load, but in reality with music, I imagine the only difference would be survival during torture. Bigger heat sink, bigger output inductors translate to more heat leaving faster. As far as musical character and raw sound quality, I couldn't tell a difference.