Sound quality impact - preamp vs power amp?

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.

hilde45 Interesting observation and something i dont have difficulty to figure out....

If i upgrade my audio system i will buy a Berning ZOTL tube amplifier that can also work like a pre amplifier with my Sansui AU 7700 which can work like a separable or like an integrate power and/ or pre-amp....(Sansui Au 7700 is one of the more flexible amp ever designed )

For this reason : tube for pre amp and S.S. for power amplification...

I feel no urge because the pre-amp section of the Sansui Au 7700 is already very good... For sure the Berning ZOTL would be better tough....

Merry Christmas...

I am generally in agreement with the line of reasoning advanced by threeeasypayments.  But you need to decide what you are trying to accomplish.  

Are you trying to make a change that will give you an incremental improvement in sound quality?  Or are you ultimately wanting to achieve a top tier listening experience?

If it is the former, then replacing the weakest link, if you can determine with certainty what that is, can accomplish that.  If you go that way, don't buy anything your can't resell or return with minimal loss.  If the later, then the following comment needs to be the foundation of your thinking.

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.

If you want to get from good to great, it is a long hard road, but that road has to start with selecting a high quality speaker that is capable of functioning well in your room and setting up that speaker in the room to minimize contribution of the room's acoustical properties to what you hear at your main listening position.  If you don't get that right, nothing else you do is going to make a huge difference, and you will never get from good to great.  Believe me, I know.  I spent decades chasing better sound through random equipment swaps.

 Four years ago I had a room full of great gear (and it wasn't cheap, by the way) that sounded like crap. Now,  having changed only one component, I've got outstanding performance.  Better than half of the improvement was due to optimizing speaker and listening position, utilizing standard room treatments to address low frequency ringing, and addressing floor vibration and isolating equipment from the floor.  All of that work, with the exception of dealing with the floor, was relatively inexpensive.   It's value proposition was off the charts. 

Good luck!

@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?