Amp advice for Sound Lab M-2's


Looking for opinions for a amp to use with my Sound Lab M-2 speakers. I am down to considering the Bryston 7b – SST, Parasound JC – 1, and the new Sanders Sound ESL amp. The former owner of the M-2’s used a Pass X-350, but I found that it sounded dry, and very thin. No warmth at all. Lots of older Krells out there, great bottom ends, but again often very cool sounding. I’m not that familiar with the Levinson’s, another option, maybe. The Sound Labs do need a good honest 300 watts > 8 ohms, and 600 watts > 4 ohms. Most amps don’t have the combination of voltage and current ratings to handle the speakers. I am leaning towards the Brystons. Overall they seem to be an amp that is easy to live with, while maybe not the best over all, they do a lot right. Ideas and experiences appreciated. By the way, the listening room is 23x21, with a ceiling that is 9 feet on one long wall, and slopes up to 16 feet on the other long wall. 15 feet of the highest long wall is open right in the middle of the wall. So the room can really suck up speaker output. Thanks.
128x128gammastrep
The best Soundlabs I've heard were with tubes. Wolcotts are popular with SL users as are Atmasphere amps. VTL MB450 and up and possibly some ARC amps are worth considering. A used ARC VT200 MkI (better than the II imo) would be a cost effective solution.

I'd definitely explore the tube amps (and preamps). The M2s are outstanding speakers and they will provide detail and imaging and bloom and air and everything from lows to highs with great non-fatigue if you marry them to a good tube amp.

Let us know what you hear when you get it all together.
I have had M-1's for about three years, about 9 months ago getting the new PX panels. Initially, I was powering them with a hybrid tube amp made by the Moscode people with good results (this proprietary design was built on the old 600 with two power supplies and a bunch of other goodies on two chassis). The only problem was that there was not quite enough punch to the sound (I listen almost exclusively to classical music). I then changed to the Bryston 14B SST with excellent results. I had the amp upgraded to the Swedish choke and things got even better. For some reason, SL owners avoid this amp (maybe because they think it is too cheap).
Gammastrep, your speakers are fundamentally different from box speakers as you know. The impedance curve is the result of 2 factors, neither of which has anything to do with resonance.

The result is that the 'conventional wisdom' about using a transistor amp to make the speaker sing is wildly inaccurate.

first, read
http://www.atma-sphere.com/papers/paradigm_paper2.html

Your speakers are a Power Paradigm technology, so voltage-source power amps like big transistor amps are all going to have similar issues- too bright in the highs and not nearly enough bass. If you think about it, lets try the example of a 600 watt transistor amp. Into the bass, which is over 30 ohms in some areas, that amp will only make about 150 watts. IOW, any 200-watt tube amp will be able to keep up with it, as a tube amplifier will be able to deliver substantial power into an impedance like that. Any time you mix Voltage and Power paradigm technologies, you will get a tonal anomaly, in this case too much highs and not enough bass.

The bottom line is that you need to seek a tube amplifier if you wish to get the most out of this speaker. As you have noted, that tube amp should be capable of some power. IME you will need about 200 watts per channel to get things happening.
Ralph;if you pop your head back onto this thread;I have m2's with impedance mods;would your 60 watt amp with the autoformers drive these;I don't listen to large SPL's on my m2's; music is mostly vocals,jazz and acoustic but sometimes pink floyd does shown up.