Since selling my VAC 70/70 Signature, I've been using and old Bryston 4BST with surprisingly good results. Most of the amps I've used with the 40.1's have sounded great in their own way, with only two exceptions:
- Musical Fidelity NuVista M3 was awful... flat and uninvolving
- McIntosh MA2275 seemed underpowered and soft. A pleasant sounding & good looking amp... just think it would pair better with more neutral, higher efficiency speakers.
Amps I have liked with M-40.1's:
- McIntosh MC275 MKV - really nice! Would not hesitate to go back to this pairing.
- Plinius SA-102 - a very solid performer, but slightly dark with the very organic M-40.1's. A well built amp.
- VAC 30/30 MK III - the best midrange I have ever heard! A bit underpowered if you like it loud... but this amp is special. I can see myself owning it again some day. A pair of these monoblocked (30/70's) would be incredible.
- VAC 70/70 Signature - more neutral than it's little brother (30/30), but this amp is awesome with jazz, vocals and orchestral. I sold mine because it was getting up in age... and at 130 Lbs it was too heavy to manage as it started needing some repairs. Great amp if you can deal with the massive size and weight.
- Bryston 4BST - this one caught me by surprise! At only $1,300 used, I was not expecting this to sound as good as it does, but it really does have nice synergy with the big Harbeths. Very neutral and surprisingly musical. The Bryston is not at the same level of the MC 275 or either of the two VAC Renaissance amps... but at a fraction of the cost on the used market, it's a strong value play. With regards to SS amps and the M-40.1's... I put the Bryston ahead of the Plinius SA-102... but would go with the Plinius if paired the SHL-5's (which I also owned) because I found the SHL-5's to be more neutral (almost bright) compared the the 40.1's.
I have a VAC Phi 200 on order that I hope to have in a week or three. I'm thinking it will be a synergistic match with the 40.1's.
