Personal speaker evolution

Definitive technology 5.5 channel
B&W 802
B&W 800D
B&W 800D with complete 7.5 channel surround system inc. sub
Back to two channel
Rockport Altair
Rockport arrakis
Magico Q5
Done!

Proac 1.5
Avalon Opus
Piega P-10
Piega C-8
Kharma 3.2
Marten Coltranes
Marten Birds
Innersound Kayas
Evolution Acoustics MM2

1991 Linn index (first hifi set up. Sold perhaps completely the wrong setup for electronic music but oh well...)
1991 Linn helix (index not sounding anywhere big enough,)
1995 Cerwin Vega AT40 (a lot of fun but ideally needed a big amp)
1998 present Rega Jura.

Beginning to demo speakers to replace the Juras which are switching rooms!

You probably want a 5 channel amp. For what you have Marantz or Anthem or NAD are all good bets. They give real power. I'd personally go with NAD or Anthem as their amps seem to power all channels and don't get overloaded (from what I hear as I only run two channel). I have an older B&K St140 that would power two of your channel nicely. Actually it's a good amp for the price as it is pretty powerful. Then you can get a nice three channel amp for your fronts and use a pre/processor. If you went that route, you keep your upgrade options open as you can just change to better amps later on or eventually save up for a strong 5 channel amp or even just get a new processor when the latest changes.

Spendor LS3/5a bw (1992, new), KEF LS3/5a Raymond Cooke edition (2006, still new), 1992 Martin Logan Aerius (2011, used).