Preamp for Aesthetix / Atma-sphere


Hi

I have the Aesthetix Io Eclipse with volume and dual power supplies, Atma-sphere MA-1 monoblocs (140 watts) and Audiokinesis Dream Maker (93 db sensitive) speakers. These are great components. My question is about system synergy, how to make them play together.

I have been running the Io direct to my amps since I first bought the Mk2 version back in 2004. At the time, I had a Krell FPB600, and in that context, it was a blessing, and a great step up from the Krell KAV 250p preamp. I'll never forget my first impression with the Io - it was like going from the wooded hills up into the mountains. There was no going back.

With volume, the Io functions as a preamp. It looks like a preamp. Someone here on A-gon said going direct is best - which I interpreted as: it IS a preamp! So I thought, OK I have a combined phono and preamp - problem fixed. But it wasn't.

From recent testing I have finally become convinced that the Io does benefit from a separarate preamp. Even if clarity and detail is better going direct from the Io to the amps, the punch and "here-ness" of the music is clearly better with a preamp in the chain, at least in my system.

Trouble is, which preamp? I am testing a small solid state Musical Innovation preamp, which helps with the punch but veils the music. An optimal solution might be the Aesthetix Callisto, preferably with dual power - but I don't have the space, and I already have a lot of tubes and tube heat. I have space for one or possibly two boxes.

From what I have heard so far, a solid state might do the job well (in my tube-rich context), however it should not impart any s-state artifacts or reduce the resolution from the Io Eclipse.

The ideal would be to test a few tube and s-state preamps, and then decide. However, this is difficult where I live, so advice is welcome.

My question relates to my own setup of course, but is relevant for everyone with a top phono stage on the one hand and amps on the other. What is best in the middle?

From recent testing I have learned that problems that I thought were related to the speakers, the phono pre, the pickup and so on, were in fact related to the preamp issue. For example, the Dream Makers straight from the Io may sound a bit lazy and washed out in the bass, very clear in mid and treble but not fully embodied. Plugging in the solid state pre, the situation becomes dramatically different, now the speakers are driving, propulsive. Very enjoyable, but some detail is lost and some transistor things added that I don't want.

So I am looking for a solution with most of the plusses, and not much of the minuses. The preamp must be fully balanced with XLR in / out.
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Ag insider logo xs@2xo_holter
Jafox, do you have more details on the RCA 12BH7 that worked magic - ? These tubes can be found, but I am not sure is it the right one.
"The whole thing feels right, bass, vocal and everything is more filled out everything working better together". Based on that description it seems that the preamp is providing "more" not less information. The direct route appears to be omitting significant vital details of your recording. The Einstein is presenting the more complete music signal.
Charles,
O_holter - I first learned from another A'gon member of the magic of the RCA 12BH7 in the Aria WV5 preamp. He was right on about this vs. the 7602 that I have liked there. I then tried it the CAT JL3 amps in the 12AU7 socket and the same miracle….wow. And then it made its way to the APL Denon CDP with a major improvement of performance. Alex of APL was telling all not to use this tube in his players due to higher current demands but as this player on had one tube for the 2 channels, it worked mighty fine for years.

The major strength of the RCA 12BH7 is new level of clarity. This amount of grain caused by the other tubes shows how the RCA removes the smearing from note to note as well as lower-level details (percussion specifically) previously hidden.

As for the Einstein vs. the Callisto Sig., these both portrayed space with aplomb which says a lot as so few line stages truly get this right. To hear these two side by side for just a couple hours did not give me enough time to become familiar with the pros/cons or to pick a "winner". There was no WOW factor here like there was when I got the Aria WV5 a year or so later.

The coolest thing about the Einstein was that you can optimize the tube for each line input
Jafox (System | Reviews | Threads | Answers | This Thread)

I forgot about that, an attribute definitely worth mentioning.

As for the Einstein vs. the Callisto Sig., these both portrayed space with aplomb which says a lot as so few line stages truly get this right. ....Jafox (System | Reviews | Threads | Answers | This Thread)
Agree, and in our test the Callisto threw a larger but less specific sound stage with more bloom.

The Einstein sounded "faster" overall and the extreme highs had more sparkle and drive than the Callisto. Some in the group preferred this and some not.

The Callisto and likely the Atma-Sphere can be tuned for more sparkle with tube choice. For Aesthetix, Siemens is an option that delivers predictable results. It's not my favorite tube for that circuit but many people love that combo.
Very interesting!

Albert - I use very low noise Telefunken in the Io, as you've written many times, these tubes are critical, and they help in the second and third gain stages also. The pair of Siemens is for the Einstein phono input, based on advice from Brent Jessee. I am enjoying the Hytron 12au7. Thanks also to Jafox, I've ordered a RCA 12BH7.

Space with aplomb - yes, and momentum, drive. Very engaging. I am playing the Vermont LP, and especially the 45 rpm bonus single. The sound is glorious, a bell strikes forcefully, the sound hangs on in the room. It may be a coincidence but I've found out that this German preamp likes kraut. Especially, ambient kraut.