I received an email concerning this topic. I was not aware it had drifted from Atma-Sphere versus Mark Levinson to Aesthetix.
I've listened to dozens of preamps including the Atma-Sphere MP-1, but not the specific Levinson mentioned in the topic.
I should begin by stating that I prefer the Aesthetix Io and Callisto Signature (dual supplies) over any other phono and line stage in the history of audio, regardless of price.
I owned Aesthetix from the very beginning. I'm responsible for corrections in the Io RIAA curve, helping with the faulty Mil spec resistors Aesthetix was shipped, and I am the person who first suggested and then implemented the concept of dual power supplies. (I must confess I was inspired by my Mike Elliott designed EASE Magnum!).
This first conversion to dual supplies was on my product shooting table in my photo studio. I soldered changes to the circuit from faxed diagrams and technical data sent by Jim White (owner of Aesthetix) while he was still employed as a designer for Theta Digital.
That was a long time ago. Jim White's fame has risen as he continued to implement multiple small but important improvements in both these flagship models.
My current pair are the absolute latest versions and after break in, I completely re tubed them with NOS Euro and USA glass. (My choices are posted here at Audiogon with link provided below.)
Now instead of just being certain that these are better than anything else, I have completely stopped wondering (or even considering) any other product as a replacement. A very difficult state for me to achieve.
Here is an old post where I discuss (no longer applicable) early technical problems the Aesthetix gear had, and full disclosure of my tube rolling ventures.
http://audiogo1.iserver.net/cgi-bin/forum5.pl?aamps&980918116&read&keyw&zzaesthetix
As for balanced versus single ended, there are advantages to each. My test was not linear as my previous single ended cables were Purist Dominus fluid, Rev B. The balanced cables were Purist Primus Ferox, only available to the Japanese market. I have these because I do product photography for Purist (as well as a dozen other high end companies) and having completed the photo session and listening to them, I fought to keep them.
My previous comparison was between identical (Rev B fluid) Purist Dominus in both single ended and balanced. That decision was very difficult, as I heard much of what Valin describes in his review. I refer to this as loss of bloom and space, particularly in the midrange, most obvious with well recorded LP's of solo piano and / or female voice. Like most audiophiles, I am familiar with these two instruments and it's easy to make critical judgements.
I suspect the superiority of the Primus is what tilted my decision to run balanced, so both answers are correct, depending on the cable chosen.
Here is the link to my system where you may see and read how I applied Purist cables.
http://forum.audiogon.com/cgi-bin/fr.pl?vaslt&1022712214&read&3&4&
As for my run from Walker Turntable to Io, it is a balanced Japanese market Primus, BUT it is wired at the source (Walker Turntable) as single ended by following the pin configuration worked out between Loyd Walker, Jim White and Jim Aud. I choose to do this because I prefer the more robust construction of balanced connectors for this application.
To achieve this I ordered a new mount plate and cryo treated tonearm wires from Loyd Walker, balanced connectors from Aesthetix and re-terminated according to instructions.
The Io is a TRUE balanced circuit, but the phono input stage is single ended internally regardless of which connector is used. My choice of connector was for quality and maintaining a solid connection in tight quarters with an extremely heavy cable (Purist) and has nothing to do with operating my Koetsu as a balanced source.
Hope this helps rather than confusing the issue. The short answer is, Aesthetix is the best there is regardless of how you terminate interconnect. It's a good problem to have in my opinion, everyone gets ultimate performance according to what pleases them.
Having CHOICE in terminations with two superb sonic signature as well as the possibility of operating single ended as true phase plus or phase minus output.
I've listened to dozens of preamps including the Atma-Sphere MP-1, but not the specific Levinson mentioned in the topic.
I should begin by stating that I prefer the Aesthetix Io and Callisto Signature (dual supplies) over any other phono and line stage in the history of audio, regardless of price.
I owned Aesthetix from the very beginning. I'm responsible for corrections in the Io RIAA curve, helping with the faulty Mil spec resistors Aesthetix was shipped, and I am the person who first suggested and then implemented the concept of dual power supplies. (I must confess I was inspired by my Mike Elliott designed EASE Magnum!).
This first conversion to dual supplies was on my product shooting table in my photo studio. I soldered changes to the circuit from faxed diagrams and technical data sent by Jim White (owner of Aesthetix) while he was still employed as a designer for Theta Digital.
That was a long time ago. Jim White's fame has risen as he continued to implement multiple small but important improvements in both these flagship models.
My current pair are the absolute latest versions and after break in, I completely re tubed them with NOS Euro and USA glass. (My choices are posted here at Audiogon with link provided below.)
Now instead of just being certain that these are better than anything else, I have completely stopped wondering (or even considering) any other product as a replacement. A very difficult state for me to achieve.
Here is an old post where I discuss (no longer applicable) early technical problems the Aesthetix gear had, and full disclosure of my tube rolling ventures.
http://audiogo1.iserver.net/cgi-bin/forum5.pl?aamps&980918116&read&keyw&zzaesthetix
As for balanced versus single ended, there are advantages to each. My test was not linear as my previous single ended cables were Purist Dominus fluid, Rev B. The balanced cables were Purist Primus Ferox, only available to the Japanese market. I have these because I do product photography for Purist (as well as a dozen other high end companies) and having completed the photo session and listening to them, I fought to keep them.
My previous comparison was between identical (Rev B fluid) Purist Dominus in both single ended and balanced. That decision was very difficult, as I heard much of what Valin describes in his review. I refer to this as loss of bloom and space, particularly in the midrange, most obvious with well recorded LP's of solo piano and / or female voice. Like most audiophiles, I am familiar with these two instruments and it's easy to make critical judgements.
I suspect the superiority of the Primus is what tilted my decision to run balanced, so both answers are correct, depending on the cable chosen.
Here is the link to my system where you may see and read how I applied Purist cables.
http://forum.audiogon.com/cgi-bin/fr.pl?vaslt&1022712214&read&3&4&
As for my run from Walker Turntable to Io, it is a balanced Japanese market Primus, BUT it is wired at the source (Walker Turntable) as single ended by following the pin configuration worked out between Loyd Walker, Jim White and Jim Aud. I choose to do this because I prefer the more robust construction of balanced connectors for this application.
To achieve this I ordered a new mount plate and cryo treated tonearm wires from Loyd Walker, balanced connectors from Aesthetix and re-terminated according to instructions.
The Io is a TRUE balanced circuit, but the phono input stage is single ended internally regardless of which connector is used. My choice of connector was for quality and maintaining a solid connection in tight quarters with an extremely heavy cable (Purist) and has nothing to do with operating my Koetsu as a balanced source.
Hope this helps rather than confusing the issue. The short answer is, Aesthetix is the best there is regardless of how you terminate interconnect. It's a good problem to have in my opinion, everyone gets ultimate performance according to what pleases them.
Having CHOICE in terminations with two superb sonic signature as well as the possibility of operating single ended as true phase plus or phase minus output.