Upgrading form Pass integrated amplifier to a better one

Hello,

Currently I have a PASS INT-250 integrated amplifier . The Pass INT-250 is a very good integrated (in my system it was overall better than Plinius Hiato, Gamut D150se, Mark Levinson 535, Vitus RI-100,  Accuphase E-470 and some others) but I can't get rid of the feeling that I miss some explosiveness (drum kicks for example) and micro details.

I know that its not the speakers. The new Sonus faber tradition I have are much more open, dynamic and airy than previous Guarneri Evos, Elipasas SE and Amati Anniversarious I used to own. And before buying them I auditioned the Serafinos with Audio Research separates and it was the amazing combo. But I really prefer not to go the separates road ( ICs, power cords and space contribute to financial constrains also) and even so I like the combo of Pass and Serafinos overall but from time to time looking for some better integrated on the market.

Currently I presented with a good opportunity to buy latest Gryphon Diablo 300 integrated or latest just released Accuphase E-650.  No possiblilty to demo them, so I am asking here on the forum if anybody can comment if Gryphon Diablo 300 or Accuphase E-650 will be better integrated than Pass INT250 overall and especially in terms of dynamics, micro details and harmonics.

Any advise and opinion would be very appreciated.

My system: Esoteric K-05x, Pass INT-250, Sonus Faber Serafinos, all cabling are the Shunyata Sigmas.

Room is 12" wide by 17" long. Listen mostly acoustic jazz and chamber classical on low to moderate levels.

Thank you.