Dang! It is that dac that's the problem. I still need to switch monitors to make sure, but the green and red lines are quick measurements with the Qudelix dac. The blue line is the SMSL DO100 dac. It seems pretty obvious.
Unfortunately, I'm outside the Amazon return window for the SMSL DO100. Should I contact the manufacturer for a replacement? It's the last thing I thought would be the problem. So, am I right in that the dac is the reason for the R monitor dropoff at 5kHz? Could it be my computer?
If it IS the dac, that's pretty bad. First the Topping D50 with a similar issue, and now SMSL? Really?
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