EMU-0404 output schematic wanted

Joined 2002
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Hey George,

Here's one for the PCI card:


My experience is that the scratchiness comes from cold solders and from dried-out output caps. There should be 4 of them, right between the DAC and the opamps. I had also removed the muting transistors from my 1212m.

There's what looks like the USB version, but I wouldn't know for sure. I pulled it out of a Russian (?) forum, unfortunately the script causes links to totally break when I paste them. The caps are the 47u units C80 and C81.

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Joined 2002
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Thank you Sangram for the treat !
The distortion is not low. It's some 0.1%. Plus the headphone out started clipping (1st attachment).
Yesterday I replaced four dual OPamps, two at line out and two at headphone out. No change.
PSU is OK. I guess it's either the diodes or the FEts.
There are many of these 3 legs. 11 at line out, 7 at headphone out. Marking 10XUJ and 15Du
The distortion as probed on main level pot is on 2nd attachment.
I don't know what has happened. The output distortion was normally at the third decimal place. In general the EMU was a slightly better performer than a new Motu M2 which I have borrowed from a friend.


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