Which 300b amplifier for Devore O/96

Myself and several enthusiast friends did a shoot out of sorts between a number of amps on a pair of O/96s. The preamp used was a CAT SL-1, a modest Rega TT with the CAT phono stage and a decent digital system with a transport through a Thor Audio DAC.

The amps used were: old Mastersound 32B integrated, Audio Note 300B parallel SET, VAC Phi 200 and Atma-sphere M-60s. The clear winner by a significant margin were the Atma-spheres. When bypassing the Mastersound's internal preamp with the CAT this amp came in second followed by the VAC. Last place was the Audio Note. There was a 100% consensus.

When compared with the M-60s all other amps sounded restricted and confused. This was especially true of the SETs. When you got above low volumes the SETs had a very obvious tendency towards homogenization of the presentation. Only with the M-60s did the sound truly leave the surface of the speakers and these were the only amps to offer a truly balanced presentation.

I cant stress enough the need for power with these speakers and also how these speakers love to be driven by OTLs. Even though many may disagree, I dont think that 300B SET power is enough to let these speakers truly breathe. 
 

You stated you are interested in 4 amps, but you listed 5. Which ones are you interested in because I am not sure if it’s 4 or 5....and if 4 which ones??

@essrand  The O/96 is a great speaker; 2dB less efficient than my Classic Audio Loudspeakers. This is just my experience, but the power of a single 300b is simply insufficient on *my* speakers. Unless you're in a small room or never listen with volumes past 80dB, IMO 7 watts just isn't enough power.

I find about 30 watts is a good minimum, if its clean power. I have a type 45-based amplifier (which is push-pull); it makes the same power as a 300b SET. Its simply not enough power on my speakers for a satisfying volume. Now SETs are different from most amplifiers in the way they make distortion; that distortion interacts with the human ear/brain system to make you think they are louder than they really are. As you turn the volume up, this distortion (higher ordered harmonics) first tends to show up on transients. This is why SETs are often credited with being 'more dynamic than their power would suggest'; a common paraphrase you see in SET reviews.

So if I were you, and you want a 300b-based amplifier, I would go with a push-pull 300b amp. It will be making about 30-35 watts which will really help out a lot. There are plenty to choose from.

Yeah its 5 not 4 amplifiers.

@atmasphere @jsautter you guys have given me fodder for thought.

I feel like my Coincidents were powerful enough. But now you are making me doubt that. Will put those amps back in, listen more and get back.

So I am guessing out of my choices your vote would be for the Nagra 300p (its a push-pull 300b, 20W).