Thanks for the nice words. Regarding:
I shot off an e-mail today to specifically to Mark O’Brien about whether any of the inputs numbered 1, 2, 3, can be used as true pre-amp out.I’ve been assuming that the rear panel of your Sphinx looks like the following, which is how it is described in the manual and is how it appears in numerous other rear panel photos I’ve seen:
http://rogueaudio.com/Images/sphinxrearlrg.jpg
It would be the "Output Var" jacks that would be used to connect to an external power amp, assuming those are present on your version of the Sphinx. I would definitely not expect inputs 1, 2, or 3 to be suitable for that purpose.
Regarding the weight of the Ayre V-5xe, while the ad I linked to indicates 75 pounds, apparently for its shipping weight, both the manual and the description at the Ayre website indicate that the amp weighs 55 pounds.
I would think that the magic of good sound would lie first in the pre-amp, not necessarily the power amp, unless it grossly under powered. Though, from my limited understanding of power amps having owned a few, power high current, low noise and especially low THD and IMD are the requirements to make a qualitative jump in sound quality.First, I would ignore THD and IMD specs in just about all cases, as they have little if any correlation with sound quality. Although I would be cautious about a power amp having THD numbers that are extremely "good," as that may be indicative of heavy-handed application of feedback in the design. Which in turn can result in excessive Transient Intermodulation Distortion (TIM), which is not normally specified, as well as excessive amounts of the specific components of harmonic distortion that are most objectionable (even though the TOTAL harmonic distortion may be very small).
Second, I am not a believer in generalities about the relative importance of preamps and power amps. It depends on the specific case, IMO. And in the case of a modestly priced integrated amp employing a tube-based line stage and a class D solid state power stage, my instinct is that it is more likely than not to be the power stage that is the sonic weak link.
Regarding the ARC 100.2, my biggest concern would have been the possibility that due to its age it would no longer sound as good as it once did, and/or that it would develop age-related problems in the not too distant future.
Finally, I have no particular knowlege of AVA products, but you may want to seek out posts on one of their products that have been made here by member "Schubert," who owns and has raved about one of them (I don’t recall which). I have particular respect for his sonic judgments. To add a bit of context to that, btw, I'll mention that as in my case most of his listening is to classical music.
Good luck. Best regards,
-- Al