My version of ProtoDAC

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:

Modified schematic for download:
https://drive.google.com/drive/folders/1TICxH7apZRNv2uVtlCqj_Q550ItMk0Lu?fbclid=IwAR2H6jWRzQcvmqxF5hjxphH14FsdPm1ecAs6FAABWiFAx5M4kGDsD8UPjvc




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Hi Vencent,
thank you for sharing your interesting work! Very nice.
PS: your github link do not work to me.

Sorry, my bad.
The link should be fine now.

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.)

Do you recommend a reclocker or isolator?

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.

Thank you! i am using a LPS and RPI 3 Version B. So, I’m on the safe side :wink:

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