Your experiences with system synergy

Not too surprising. Yes, that nebulous / nefarious concept of "synergy" is crucial. Everything matters for a good amp match, not just speakers: preamps, source, volume level, music selection, and YOU.

Psychology is a factor too. If you’re expecting miracles from a new amp (or whatever), that’s more often a setup for disappointment. On the flip side, I’ve been loaned "next level" amps by my dealer at times when I was already "perfectly happy" with my system. No obligation or risk on my end. I didn’t expect anything, other than a bit of fun experiencing the new amps followed by their return. Twice now that has left me blown away by the new amps, and scrambling to make their purchase. Haha.

Preamps have proven a more difficult upgrade for me. They don’t overtly change sound as much as power amps, but somehow synergy is even more key in this slot. A few years ago I purchased my VAC Master preamp, and it didn’t totally blow me away until it was later matched to the VAC Master 300 monoblock amps. Fortunately I kept it until then, because I had been flirting with selling it and just sticking to the Ref 6. It was really weird, in some ways the ARC Ref 6 seemed a better preamp match for my VAC 200iQ amps. 

It is great when you plunk down a new piece of equipment and the difference is instantly obvious and huge. That happens when one is working up to the higher echelons of equipment. But once you are there things can be different.

First, as pointed out by @audphile1, it is way too soon to make a judgement. 
 

It is too soon even if the amp was broken in. I would make sure to get at least 20 hours or hopefully more on it in your system. (If it is new… then you really will needs hundreds). Second, you want to spend at least a couple weeks before swapping back… listening to the music not trying to listen to the amp. The music you listen to over time will reveal differences. The analytical thinking is only good for glaring differences in some very obvious parameters unless you are really experienced in doing it (like you are a dealer who swaps stuff for a living).

You are likely to hear the differences when you swap back to your old amp after a good long exposure to listening to music.

Having said all that. Yes, there is such a thing as synergy.  It was not by accident I finally converged on my all Audio Research system (under my ID). In this case, dropping the DAC and amp in were earth shatteringly obvious. But I have compared very high end DACs and while the differences seemed miniscule and required lots of exposure to reveal, once revealed there was no question they had a very profound effect on my system.

qualiton is a very good amp 

what were you comparing to?

It’d be useful for you to post more details about your system and the new amp.

There are a lot of variables in play. I would not write off the new amp without a good long warm up, and ample time for the tubes to burn in (if not done during manufacturering). I’d also ask the manufacturer for input, and/or what cables theyy suggest with the amp....the synergy issue could be that simple. Give it a chance before dismissing it.

I don't have experience in high end valve equipment, but I find there is a very clear element of synergy, even in my entry-level, solid state experience. All equipment in the audio chain have inherent "voicing". My experience is that the amp and speakers are the most critical elements, but source equipment voicing also vary considerably. My amp has what I call a "punchy" presentation with slightly extended high frequency output. The speakers I have are somewhat inefficient and have a more "relaxed" presentation. Together, the amp and speakers seem to have a complementary sense of sonics. My previous set up was the opposite with forward sounding speakers and a more relaxed voicing to the amp. They also played well together.