I came across Moode Audio’s TDA1387 project by chance and was amazed by the work and decided to make my own with some modifications.
The schematic is simple, with the proper selection of coupling caps and I/V resistors this tiny DAC module sounds amazingly good. I’d say this is the best DAC that I have ever had - warm, transparent, musical, rich, detailed, relaxed, and analogue. The bass response is surprisingly deep and punchy. The DAC is powered by Pi 4 thru a LC filter.
Coupling cap: copper foil in oil
I/V resistor: metal foil
Original Github tutorial:
I have also made a YouTube demo in case you’re interested:
I have just finished the dac and it plays wonderfully - indeed analog!
I’m very curious to see how it sounds in direct comparison with the other DAC boards.
I used a different GPIO header so that I can put something on top (OLED, e.g.)
Thanks for your feedback.
I’m not a big fan of reclocker, it may sound better but I’m not sure.
Regarding the isolator, I’m still testing the sound quality but it seems like complete galvanic isolation is not necearrily better. Now I’m testing an isolated version with NVE IL715 with the grounds of DAC and Pi 4 shared at one point (star topology), which is also connected to the earth.
Although the high frequency noise from Pi 4 is higly attenuated by the LC filter, I would still recommend a LPS as the power source.
Lastly, as a warm reminder, it would take about 10hrs for the coupling caps to break in.
I am still enthusiastic about the Dac board. Very well done.
If there are any improvements or new versions, please let us know here!!!
If I may have one wish, I would like to have a potentiometer volume control as option. When I connect your ProtoDac to my power amplifier, the sound is still clearly audible at 1% volume. I would like to turn that down further.
Thanks.
As mentioned earlier, I’m working on a GI edition (galvanic isolation) which should further improve the sound from TDA1387. The board is ready but it just takes me some time to validate the improvement.
The standard version is changed from LC filter to CLC filter, upgraded the FW caps to KZ caps. These changes should add richness and make the high even more smooth. Additionally, a TDA1543 version of ProtoDAC will also be available soon. Will keep you posted.
Regarding the potentiometer, it will deteriorate the sound unless it is made of high quality components. Personally I don’t use a potentiometer. May I know the reason why you would like to further turn down the volume? At 1% the volume should be hardly audible. I’m running DietPi by the way.
Great! Thank you very much. I’m looking forward to the next, improved version and also to the TDA1543 version!
With volumio and software loudness at 6% and less it’s alway the same level of loudness. My power amp does not have a PreAmp. if using the protoDAC in my sleeping room i have to use a integrated amp to regulate the sound near silence to dream with it . But ok, i can live with it
The output volume of TDA1543 is lower than TDA1387. Refer to the volume output levels in log scale below, assuming you are listening to TDA1387 at 60% volume, in order to maintain the same level of TDA1543, the volume has to be adjusted to about 71% or 72%.
Thank you for the update Vincent!
is the GI Version only recommend for the Pi 4, or does the version also bring audible improvements for the other pi boards? I see more SMD components are used there. Are these to be soldered myself?
Very smart, that the TDA1543 is compatible with TDA1387 module and works with all versions of ProtoDAC!
No, the GI Edition is not just recommended for Pi 4. It works with other Pi but a separete power supply (preferrably LPS) is required. The quality of the LPS directly afffects the sound from the DAC. The isolation brings a quieter background and more details even at low volumes.
Regarding the SMD components, except the isolation IC, other components (including 1206 parts) will be soldered by yourself. But if you’re not confident doing that, I can solder them for you first. And leave the other thru holes parts to you.
