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 have a tube preamp and amp that works well with my speakers. They have good tubes.

I have a good integrated solid state amp that works well with my speakers.

Here’s the comparison I did. Keeping the DAC and the source the same:

(a) SS-Tube. When I run the solid state integrated as a preamp only through the tube amp, it sounds ok.

(b) Tube-SS. When I run the tube preamp through the integrated’s amp section only it sounds much better.

So, in my particular setup (only!) I can conclude that the preamp makes the bigger difference.

My tube and solid state are at similar price points. I realize that my tastes, impedance matching, etc. could be factors here, but I do hear a clear difference. Preamp more important in my setup.

@tvad 

In your scenario, one could also conclude the integrated’s solid state amplifier section makes the bigger difference (by matching your speakers more optimally)...since your system sounds better when the speaker’s are driven by the integrated’s solid state amp.

I should add that the all-tube combo beats the tube-SS combo. Does that affect your point, above?

@jaulbrich -- Your post made me laugh because it was such a compact and insightful compendium of (to modify the old jazz standard title) "All the Things We Are." I also laughed because there is this constant forgetting about what the hobby is about (in other words, that it can be about so *many* things, none superior to the others). And none of us think or say, "Someone who knows about main courses really knows about 'food' but a baker or a wine maker doesn't." No, we say, they *all* know about food. So, there is something weird that happens (sometimes) in this hobby when people want to collapse the different purposes at work into a single end, and then argue about that end.