Detlof,
I have driven my SoundLab A-1PX with Atma MA-1s, Parasound JC-1s, and now Ayre MX-Rs. The Atma-Spheres are an excellent match, no question. They have three significant downsides: 1) they produce a great deal of heat, which is unacceptable for 7-8 months of the year here in subtropical Houston, 2) they take a good hour after power on to sound their best, while the MX-Rs are at the peak within 10 minutes after startup from standby mode, and 3) they are simply not as good as the MX-Rs in several respects (timbre of bass below approx. 60 Hz, soundstaging, and - most importantly - a quality of 'light' that I find extremely difficult to describe). The MX-Rs do this better than any amp I've ever heard, and said quality contributes greatly to the sense of realism.
A short comment on the JC-1s - not the absolute best available for SoundLabs, but darn close. A truly oustanding value for money. They are a ridiculous bargain when purchased used.
Mothra, I also apologize for getting off topic. I've auditioned stacked 57s just once quite a number of years ago, and was a bit bothered by the loss of the stunning midrange coherence displayed by a single pair. Then again, I don't know how the stacked pair was 'hooked together', so this comment should be taken with a large grain of salt.
I have driven my SoundLab A-1PX with Atma MA-1s, Parasound JC-1s, and now Ayre MX-Rs. The Atma-Spheres are an excellent match, no question. They have three significant downsides: 1) they produce a great deal of heat, which is unacceptable for 7-8 months of the year here in subtropical Houston, 2) they take a good hour after power on to sound their best, while the MX-Rs are at the peak within 10 minutes after startup from standby mode, and 3) they are simply not as good as the MX-Rs in several respects (timbre of bass below approx. 60 Hz, soundstaging, and - most importantly - a quality of 'light' that I find extremely difficult to describe). The MX-Rs do this better than any amp I've ever heard, and said quality contributes greatly to the sense of realism.
A short comment on the JC-1s - not the absolute best available for SoundLabs, but darn close. A truly oustanding value for money. They are a ridiculous bargain when purchased used.
Mothra, I also apologize for getting off topic. I've auditioned stacked 57s just once quite a number of years ago, and was a bit bothered by the loss of the stunning midrange coherence displayed by a single pair. Then again, I don't know how the stacked pair was 'hooked together', so this comment should be taken with a large grain of salt.