Having had both myself, I think I can attest to that although I suspect there are a few on this forum who might disagree.
Get well soon!
I performed today some preliminary comparisons. My head still feels a bit clogged from the flu, so I will be performing much more thorough tests when I get better.
Observations:
1. The difference between using Meridian's wall wart and the CI Audio power supply are indeed very subtle. The main differences I hear when using one sets of headphones (the Ultrasone8), was a slightly tighter and more defined bass in several of the tracks I used for testing. I did not sense any major differences in the higher notes like cymbals.
2. The difference was increased a notch when I plugged two sets of headphones at a volume level that was the maximum I could tolerate (about halfway in the volume dial). The other headphones I connected was the Grado PS1000. My guess is that the extra power requirement to drive two headphones at the same time created the extra advantage for the CI Audio power supply. But again, the difference was evident only after performing several A/B comparisons, by switching the power supply as quickly as I could. I was actually afraid to damage the amp after a few of these tests, so next time I do them, they would have to be after properly shutting the unit and powering it back again with the different power supplies.
My initial reaction is that the wall wart is more than capable of handling full sized headphones at great sound quality. The CI Audio power supply provided more muscle for multiple headphone connectivity (not sure that's my use case) and an overall slight sound improvement. Having said all that, I'm glad I got the CI Audio unit and it will be staying home with me for a long time.
My next set of full tests would involve comparing:
1. Meridian Prime by itself
2. Meridian Prime + iFi iUSBPower
3. Meridian Prime + CI Audio
4. Meridian Prime + iFi USBPower + CI Audio (the configuration I'm currently enjoying)
