B&W 805s vs PSB Synchrony Two

I you want to keep your current amp, you would probably happier with the PSBs as they are technically and practically more efficient than the notoriously power hungry 805s, and will go lower.

Or you could do as suggested above and ditch the amp for something that can really drive the 805s. Well driven, the 805's are quite rewarding with better midrange and treble integration and "snap" compared with the PSBs.

Either choice would probably be an upgrade to your current system, but not necessarily because the PSB's are "better" speakers than the 805's.

For Tubes I would suggest something with at least 80W, for Solid state, as suggested above 200 watts/ch or something with a TON of current would punch the 805's ticket.

Assuming the choice is $1749 for the Synchrony Ones, or the same amount for an amp, here are some ideas in that range. Frankly, it would be tough to beat the quality of your current amp by a whole lot for that price, at least new. Here are some ideas:

Vincent Audio - SV-236 MKII
Used Musical Fidelity A5
Cambridge Audio Azur 840A v2
Jolida 1000RC (used now on Agon)
NAD M3 (used now on Agon)
Classe Audio cap 151 (used now on Agon).

Or look for some good separates used - like a CJ pre and something like the Odyssey Audio Stratos Extreme amp.

As for what is better - bass or midrange. Huh, well its not up to me, its up to you. What do you like better? Maybe this is a false dichotomy - enough power behind the 805's, well placed and on good stands, and you will hear some tight, loud bass for sure.