Otto,

I was only able to do that comparing whatever DAC I was using against the original transport's signal. Had to swap out DACs in order to compare. Luckily, I had a couple of friends over listening as well and agreed with me on the results of the Benchmark vs. the CIA and helping with the swap outs of DACs. The CIA does not come with a volume control. We had to use a sound level meter and compensated for any sound level difference each of the DACs we tested may have. Out of all the ones we tested, the DIYEDEN Great March had about 1 dB greater output than all the rest while the others we spot on with each other, if I remember correctly. When I have a chance later this week, I'll share my findings with my Sony megachanger as the transport. It uses a linear power supply vs. the Oppo's switching power supply. Then I'll know if I keep the CIA or sell it. Thanks for asking.