Sound quality impact - preamp vs power amp?

@tvad  Thanks -- yes, I think you're right to point out that I'm probably not doing a fair quality-level comparison (between QS and Atoll). That Pass Labs would really be the test. (And it's cold in Denver lately, so it's heat would be a bonus!)

I believe the whole point is to optimize the synergy among your components & room to best connect you to the music and stir your soul.

Bingo!

A synergistic system that stirs the emotions is the ultimate goal. This can and often does result from very unusual combinations. You cannot simply throw money at the problem either. So when I see someone is using $1K speakers with $10K amplification, and vice versa, I no longer assume he/she is a noob. 

The amp and preamp are both just as important as the other. If I spend 7K on a preamp, then I will spend 7K on an amp and probably by the same manufacturer.  Synergy is everything.