I ordered a ZERO DAC from eBay since I couldn't find a physical store with this one in stock. The DAC just arrived today in its' original box (I guessed it is because it was printed all over with Tianyun brand and ZERO description).
However, when I decided to unscrew the cover to see if I got a correct Opamp (I ordered one with OPA627), I noticed my circuit was quite different from the picture in the internet I saw before.
Now I'll make a comparison for the differences between mine, this thread, and Tianyun's site:
Here's the main circuit:
- two blue boxes on the left bottom corner should be yellow
- well, my opamps are totally different!
- but it still says OPA627 on the top (very pale and tiny text)
-the biggest two capacitors are in different color, different brand, and even different capacity! (even worse, most of my capacitors doesn't match the one in that thread too.)
-the transformer wires' color are also different
- the frequency generator label doesn't match, and those little yellow boxes are different.
Here are the rest of my circuit:
I read the post about fake OPA627 though. But no one has ever said anything about counterfeit ZERO dac yet.
Could it be that my copy is a fake one? Or they're just cutting corners, because many parts on my board look cheaper than the pictures I saw previously.