I own the Magnepan 3.6 and have run them with the Atmasphere MA-1 mk2 with and without a Zero autotransformer; the Atmasphere MA-2 mk2 with and without the Zero autotransformer, and the Wolcott Presence 220 with and without the wideband transformer.
The Atmasphere MA-1 or 2 sound remarkably similar when used without the autotransformer in that there is quite a bit of midrange bloom with a slightly softened bass, treble and microdynamics. Harmonic richness is aplenty. I suspect that the output impedance of the Atmasphere causes a shift in the frequency response of the speaker that emphasizes the midrange.
With either the MA-1 or 2 amplifier, the insertion of the Paul speltz Zero autotransfomer will yield a very balanced, detailed and dynamic sound spectrum that retains the harmonic infrastructure that the Atmasphere is so known for, yet without the midrange emphasis. There is a liquid flow to the music spectrum, especially noticeable through the midrange, that will arrest one with how real it sounds. It encompasses a musicality that eludes the Wolcotts as well as all other amplifiers that I have tried on the 3.6s. It is in this configuration that one discovers the true meaning of "grainless". Even very good amplifiers such the Pass series exudes an ever so slightly strident flavor to the music that detracts from the musicality. Almost too squeaky clean I would say.
The Wolcotts are also excellent amplifiers. They sound very tight, dynamic and also clean. Frequency spectrum is full and extended. The sound on the Maggies was essentially the same with, or without the wideband transformer (this wideband feature is primarily for electrostatic speakers such as the Soundlabs). Although I liked the Wolcott, it never made an impression on me that the Atsmaphere did. I think it lacks a bit of harmonic richness (not bloom in this case)that the Atmasphere has in exactly the right amount. The Wolcott sounds like it is almost too much in control of things. It just does not let the music flow quite like the Atmaspheres do.
I could live happily with either, but I prefer the OTL. I do not play music loud so, things may be different if I let'em rip. I did notice that turning up the volume seem to cause the Atmasphere to struggle while the Wolcotts became ever more comfortable and, more dynamic. But, this is a moot point for me becuase I don't play it loud.
