I have had good results with my Audio Aero Prima Integrated. It has a tubed pre section coupled with a mosfet amplfier . They are $600 - $700 used . I have heard a few other integrateds (well respected) costing much more that did not sound as good, all on the same speakers .
Synergy is quite important though . YMMV
Synergy is quite important though . YMMV