Anyone compared BAT Rex vs. Atmasphere MP-1?


Obviously, there is a big price difference between the two(not as big used). But, these two are likely to be in the top of the true balanced, fully differential, reference preamps available.

I'm mostly interested in the sonic differences anyone would have noticed switching between the two in their own system.
darkmoebius
Hello,

I am not familiar with MP-1 except its excellent reputation. I am familiar with REX and its the best (along with my current Joule-Electra LA-300ME) preamp I ever auditioned or used.

When I heard REX first time (using my reference tracks) my jaws literally dropped to the floor. Word "magnificent" is understatement.

Regarding the long cables - its the best if you call Victor. In this situation,I would not care at all if preamp balanced or not but if it has a buffer driver. Victor is perfect man to address your specific concerns, He is extraordinary nice person (well may be not in all his writing... ;--) ;--) He will help you and advise you. You meet daily at "Outside" and Victor will do everything he can to help you in any way possible.

Good Luck !
Simon
Rtml, thank you for the great description. I find myself leaning towards a more rich(not overly-ripe, though) and powerful sound. I had considered ARC, but since I will be buying used, I didn't want to deal with trying to decide between the Ref 2, 3, 4, or 5 to find where the "sweet spot" for price versus performance was.

Simontju, I will ask Victor. He is always great with technical advice - whether about his products or just engineering in general.
Hello Darkmoebius,

Just wanted to take the opportunity and give a plug for the BAT Rex. I don't think you'll find a preamp that dives deeper into the texture of sound as the BAT Rex. That's what I consider detail!

At the same time it does it with such a sense of authority and grace, never blinking an eye, a feeling of ease to the sound that invites one to listen in to the music. For me it is such a pleasure to own and I wish you luck finding a pre that you'll feel the same about.

best,
Tom
I would like to ask Raquel to elaborate on the Rex not being able to be on 24/7. The reason I ask is that I have mine on 24/7 (breaking in new speakers) and you have me worried. :-)
Madflloyd:

Some tubes in some tube power supplies can pass a relatively large amount of current and will wear out like output tubes in a power amp will wear out (certain tube preamps actually use output tubes in their power supplies - the ARC Reference 3 uses a 6550, and I believe the big multi-chassis Jadis used to use EL-34's). For example, when Stereophile reviewed the BAT Rex, they went through a couple of 5AR4's in the power supply over the course of several months of leaving the preamp on 24/7 (which they evidently did at BAT's suggestion). The review suggests that the BAT is fused to protect against tube blows in the power supply - you need to consult your owner's manual or ask BAT whether 24/7 operation poses a safety issue.

The other circumstance in which I would tend to think twice about 24/7 operation in a piece of equipment using small-signal tubes (i.e., tube preamps, tube DAC's, tube tuners) is if the tubes are run near their maximum voltage rating. Basically, such a tube will face the same wear issues that an output tube in a power amp will. It did not escape me that the Rex is said to run really hot, but this could be nothing more than the fact that it has a ton of tubes in it - I don't know how its various tubes are run relative to their maximum voltage ratings.

If, however, a tube preamp has solid-state rectification and does not feature a hot-rodded tube circuit (that would be the vast majority of them), I will run it 24/7 in order to maximize sound quality and tube life. As for why 24/7 operation would extend tube life, please see my comments about small-signal tubes and tube performance in the following thread:

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1281657617&&&/VAC-Signature-MK2a-w-phono-users

I hope this helps.