Symphonic Line RG7 Mk5, or RG-4 monoblocks ( the RG 4 monoblocks are the best choice in my opinion with the 802D3)..... Rega Osiris integrated (you can compare its line section to the Audio Ref preamp, as it offers a "direct" mode as an amp)... Also the Rhapsody Sound in NYC imports a new line of amps: PILIUM. The importer (BOb Visintaier) has been waxing superlatives on this brand, and he has a good ear and a nice guy to boot, worth talking to IMHO (just avoid modern day ex demo, or new Goldmund amps he might offer)... Nagra amps suck by the way, for the kinda of money they want for them.... as do Gryphons & Vitus for the same reason.... imho.
There is also a dealer in SF offering the Technics SE-R1 at a good price.... Worth looking into with its companion DAC/preamp... vs your REf 6 preamp....
The new Yamaha Ca-5000 preamp & M-5000 amp, which now only available in Canada, but should be of reference quality at about 15 grand $US..... In fact you can vertical bi amp your speakers with 2 of those M-5000, for almost an "unlimited" reserves....
There is also a dealer in SF offering the Technics SE-R1 at a good price.... Worth looking into with its companion DAC/preamp... vs your REf 6 preamp....
The new Yamaha Ca-5000 preamp & M-5000 amp, which now only available in Canada, but should be of reference quality at about 15 grand $US..... In fact you can vertical bi amp your speakers with 2 of those M-5000, for almost an "unlimited" reserves....