Vintage amps - Carver, Krell

For Carver, I believe the later TFM models are higher current and would work better with speaker designs that are more current hungry and have more difficult loads.

I had an m4.0t Silver Seven prior to my current Musical Fidelity A3CR. That model delivered a lot of watts per dollar but was not high current. It sounded very good with Magnepans for example when I had them but low end was impacted at lower to moderate SPLs driving more current-hungry designs, like the OHM Walsh 5's in my system. When cranked to higher SPLs , it still sounded very good for the money with the OHMs.

For high watts/high current, if you could swing it, I would look at newer Class D amps for best sound and cost effectiveness. Wyred 4 Sound has some relatively low cost units that has attracted attention.

The Musical Fidelity Q#CR in my system cost me $600 used and replaced the Carver m4.0t. It is lower power but high current and should drive most anything in most rooms.

Among Carver amps, I'd swing towards towards the newer TFM units myself with most speakers.