Zero Feedback: Atmasphere vs. BAT

I lost count how many amps I have bought and sold in the past 10 years, but one thing I can say confidently is a stock BAT 75SE is not veil or lean. in fact, it's much more transparent than just about anything else and that's where I stopped. well, I did upgrade to 150SE.

A couple of years ago Nelson Pass (check out 1st Article on website, seems a must read for audio geeks) wrote on the subject of zero feedback. He talked about the distortion spectrum between an A circuit running zero feedback, and an AB running zero feedback, as well as the whole feedback concept creating less total distortion, but more of the complex unpleasant type. This was also covered in Stereophile, as they were gushing over a Cary 803C amp and zero feedback CJ Pre. In the back of that article the designer of the CAT Pre tried to inject some sanity in the conversation by saying it is not sooo simple.

Since I cannot listen to all the equipment in the world, I was wondering how BAT compared to Atma? From what I can tell their are fans of both with Atma perhaps being more trasnparent.

Still comes down to "Gold Plated Decibels" as a key factor if you want to have a class A set up, you gotta have effecient speakers if you want the option.

Thanks,
Scott

"...if you want to have a class A set up,you gotta have effecient speakers if you want the option."
I beg to differ.

Sorry about that Unsound.

You can purchase a Krell KSA 200 or a Threshold, or a Pass XA200 or something else in the BIG Class A Tube range like TRL Tube amps ot ATM1.

It's a lot of energy and possibly big upfront cost going that route. I stand corrected. Still looks like "Gold Plated Decibels" when you factor in your energy bill and a lot of heat in the summer if you go big class A.

Best Regards,
Scott

I just wanted to jump in and add a few thoughts, being a 20+ year Atma-sphere user (and now a dealer).

The OTL impedance matching issue with speakers is not as critical as one might think. I am currently using a 4 ohm speaker (with MA-1's) with the Speltz Zero autoformer to bring it up to 8 ohms. That being said, I am soon going to be trying a 16 ohm speaker, which I won't need the Zero with.

As far as heat, I believe I have heard it said that even class A solid state gets probably as hot as Atma amps. I can attest to the fact that the newest Atma designs run cooler than older ones, and one can always take out tubes and run with less power for summer time usage.

In my opinion, getting a great class A tube amp is the best way to get off the high end merry go round, at least as far as amplification is concerned.

And if that upgrade bug does eventually hit, rolling in NOS tubes are a great way to significantly increase the quality of sound for minimal cost.