I received my Compass just before Christmas. I've taken an active interest in audio, headphones and binaural recording for three decades, but it has been in low gear for a decade or so due to pressures of life. Plus, of course, I had more good equipment than I actually needed, and extensive blind testing had made me largely immune to most high-end siren songs.
However, rethinking my music library from the ground up made it clear that having a flexible external DAC was quite useful. The DACMagic seemed like a good solution, but then I found the audio-gd Compass, and it seemed like a more interesting piece of equipment. I ordered it and recieved it just before Christmas, and have had some limited time over the holidays to listen to it, and of course, given my background, make complete sets of measurements of its performance with RMAA and the X-Fi Elite Pro, using all three discrete OPAs.
I was gratified to see that the different OPAs performed basically identically in the Compass - Samuel Groners "Operational Amplifier Distortion" document was largely dismissive of these discrete opamps and for good reason given how he made his tests. However, as used in the Compass design they perform so well that they are barely visible in the measurements - in fact they were so similar that I had to replace them with the (generally excellent) 4562/49720 IC opamp to make sure I wasn't making some kind of error in my RMAA analysis that gave me identical results. I was gratified to see that the IC actually produced slightly more noise and low level measurement grunge. This boosted my confidence in audio-gd engineering prowess regardless of his catering to the audio lunatic fringe
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And this was perfect for my purposes - it allows me to compare amplifier topology without the comparison being tainted by significant linearity differences, or differences in noise performance. At some point in the future I will make both break-in measurements (not expecting to find any differences, but I'll test it anyway), and blind tests of the OPAs.
Do I feel bitter that I didn't get the FUN that was released just as I recieved my Compass? Well, yes, a bit, because the FUN offers one more place where it might be interesting to compare components. On the other hand, the Compass performs very well indeed, and while tinkering is FUN indeed, at the end of the day listening to music is the justification of all audio equipment and there the Compass does a great job, and with excellent versatility.
