With these horror stories out of the way and the amps dialed in as maximum pleasure- producing devices, I got down to spinning CDs and, as is my custom, taking notes. My first inclination was to replace the amp's crummy Russian 6SN7 driver tubes with some of my choice NOS but Atma-Sphere guru Mark Gilmore advised against it, preferring the amps to be judged on their merits in stock form. So be it. I had been warned that the MA-1s would sound thin and perhaps even shrill. My previous M-60s could sound thin with the wrong cables so I was prepared for the worst. But once my cables were complimentary, I never found the MA-1 MkII.3s to sound anything but sweet, extremely extended, clear as a bell, as transparent as I have ever heard any system (even the monster Shindo system the moonies enjoyed in Srajan's recent Forbidden Fruit report), and generally generous in all aspects of audio reproduction.

And I don't care what anybody says about power and its particulars as to SET or solid-state - 140 watts of Class A power is heaven in my book. I don't know if it is the massive reserves they offer or their exceptional design, but the MA-1 MkII.3s cast tremendously stable, fleshy, massively wrought images that filled my smallish listening room with loads of detail and life-sized soundstaging. The sound was entirely effortless and extended in the frequency extremes.

First CD up was clarinetist Don Byron's Ivey-Divey [Blue Note], a trio affair with drummer Jack DeJohnette and pianist Jason Moran. Trawling through their 40sish Benny Goodman-styled song book, the trio tackles "I Want to Be Happy", "I Cover the Waterfront", "Abie the Fishman" and even "In a Silent Way". The instruments spread across the listening room, easily extending to the left and right of the speakers with a tactile slam and swing that was infectious. When all three musicians were blowing full bore and all-out, the music never became congested or strained in any way. The louder and more extreme the music became, the greater the Atma-Spheres' ability to separate and reproduce every piano nuance, bass drum blast and wailing clarinet call. The Atma-Spheres' talent for separating musical details at
vociferous dynamic levels made listening intoxicating and fun. DeJohnette's cymbals were dry and splashy and his bass drum and especially toms boomed with authority. All sounds were delineated in perfect studio space. I felt like I was in front of the mixing board.

A record I enjoy for gut-busting double bass drum attack and guitar/keyboard duels is Billy Cobham's classic 1974 recording, Spectrum [Atlantic]. This is a thunderous CD with fusion drummer Cobham, bassist Lee Sklar, Moog maniac Jan Hammer and guitar virtuoso Tommy Bolin. A jazz rock classic and roaring improvisational blowout, Cobham's drum corps patterns further energize and inflame the already psychotic dual solos of Hammer and Bolin. Opening track "Quadrant 4" is a full system workout of hyper 16th-note double bass, drum rolls and screaming guitar with atonement for audio sins offered by Sklar's big-hearted bass. The Atma-Spheres offered tremendous speed -- a OTL trademark -- while the music's flagrant dynamics were delivered with ease. They didn't cover up the old recording's sketchy treble but allowed
ultimate transparency as a golden rule, good or bad. Again, the Atma-Spheres' most exceptional trait was their ability to cast massive images coupled with thrilling detail and extension. When Cobham roared around his kit, I felt every stick whack and cymbal smash as though my head was trapped inside the shells. This was entirely first-row stuff; no back-of-the-hall ambience here.

Switching to something a little more - er, modern, I played Café Brasil 2 [WEA Brazil], an excellent compilation with Ivan Lins, No Em Pingo D'Agua, Beth Caravalho, Morres Moreira, Sivuca, Elba Ramalho and other native Brazilian folk and dance artists. A lush recording with plenty of acoustic stringed instruments and Brazilian hand drums and percussion, Café Brasil 2 is my ultimate acoustic disc. As voices soared and instruments warmed the cockles of my ears, I was repeatedly struck by the Atma-Spheres' full-range super-spectacular presentation. The sound was so focused and articulate that I could see deep, deep into the recording.

Another acoustic disc with plenty of romance and tonal flavor is Quadro Nuevo's Canzone Della Strada [Justin Time], a trio of young German jazz musicians playing old Italian favorites. Performing on bass, guitar and accordion, the music is inviting and relaxing, the kind of thing you should hear around Greenwich Village but never do. Here, the music had so much micro-dynamic thrust and inner detail that I just wanted to listen forever. You could feel every smack of the upright bass, every string nudge of the guitar and the warm accordion swell. Real life detail, sweet sounds and big-bottomed girls. Compared to my BAT VK-75, the Atma-Spheres just offered more of everything: More detail, more extension, more transparency, better soundstaging, greater micro and macro dynamics, more extended and luscious high
frequencies. The only area wherein the BAT bested the Atma-Spheres was in overall warmth. The Atma-Spheres, though able to go very deep with rock-solid imaging, did not produce the level of bass warmth that the transformer+ BATs do. Could I live with one and forget the other? I don't know. This is not a small quibble. I prefer warmth. That is why I love tube gear in the first place. Alas, for $4K more, the Atma-Spheres produce an assortment of sonic virtues (in light if oblong and hard-to-place enclosures) that is nearly irresistible if -- and that is a big if -- you have the cash. But as most of us know, this audio game is a matter of priorities. Put another way, bills get deferred, old cars driven, holes are attached to socks and endless trading goes up and over.

Just for fun and mostly because the honchos at Atma-Sphere insisted on it, I included their MP-3 preamp in the reviewing equation. Now, my Shindo Monbrison is without peer in my book unless you consider the even more upscale Shindo Allegro or Shindo Catherine models. But as I was using an Audio Research pre at the time when this review was assigned, I agreed to include the MP-3, not the least because I had reviewed it previously for SoundStage!. The MP-3 did add some much-needed warmth and low-end slam to the MA-1s but came with a loss of fine inner detail and micro dynamics and an overall sense of veiling that I found unacceptable. Still, the added warmth was an improvement at least in that one regard.

The Atma-Sphere MA-1 MkII.3 Silver Edition 140-watt monoblock OTL amplifiers are winners in my book, with only slight caveats. They produce massive sit-down-and-rest-a-spell images that are rock-solid yet liquid and entirely engaging. That clash o' words is an entirely accurate representation of the Atma-Sphere voodoo because us audiophiles want both the liquidity of tubes and the unwavering portrayal of soundstaging and dynamics that only the best components can deliver. I never felt less then extremely impressed with the MA-1s' super-fast dynamics, effortless back-to-front, top-to-bottom soundstaging and overall sense of flow. While I do attribute some of this flow and articulation and micro detail to the Shindo Monbrison -- since a loss of same was very much present when I replaced the Monbrison with the MP-3 -- the MA-1s' gigantic imaging, excellent dynamics, frequency extension and potent music-making remained. These are world-class amps that deserve your attention. Avoid them only if you live in the tropics.
Atma-Sphere responds:
Hi Ken,
Let's see - only two comments.

1st. The stock 6SN7 tube is Chinese, not Russian. We've not used the Russians in years.

2nd. Warmth. (I just have some comments if that's okay.) Tube 'warmth' (no pun intended) is actually a subjective measure of the amp's even-ordered harmonic distortion, which the MA-1 has less of then the BAT VK-75. So it correctly would not sound as warm, but it should sound more transparent. For the same reason, with less distortion, lower-level details are more easily revealed.

As audiophiles we describe this even-order harmonic distortion several ways, depending on the amount of it: Warmth, bloom, excessive bloom, fatness and finally muddiness.

I certainly understand 'liking' warmth. In the 1960s, General Electric conducted tests and discovered that people will tolerate even-order harmonic content up to 40%! while at the same time not tolerating even a fraction of a percent of odd-order content.

So I am simply saying, yes, it has less warmth, but that is because it is more accurate. The rest of it has to be taken up elsewhere....

BTW, you didn't mention what you thought of the A/B feature, so I am curious what you thought of it.

Anyway, thanks for the wonderful review. I apprciate the time and effort.

Ralph Karsten

I would like to thank you for taking the time to review the MA1 and offer the following important comments for your consideration.

1) We apologize for the lack of updated documentation accompanying your shipment. That, along with the labeling of the switches, is in the final stages of completion.

2) You only address the A/B switch in a cursory way. One of the main reasons that this feature was added was to address the heat issue, which of course you dramatize extensively. We also took pains to make sure that the circuitry involved had little ramifications sonically. So I think that it would only be fair if you made more of the fact that operating the amp in A/B mode generates significantly less heat with little sonic sacrifice.

3) The fact that your socket was burning up had nothing to do with biasing the amp in A/B mode rather than A mode. It had to do with the fact that your wiring and circuit protection is substandard in your home. You have created a damaging and inaccurate impression that implies that you can burn your house down if the amps are not biased correctly. What you can do is burn your house down if your wiring is not done properly and if you don't have proper circuit protection - in other words if your house wiring is not done to code. You could have plugged in a space heater and seen the same effect, perhaps with more serious consequences. So perhaps this episode alerted you to a more serious problem you have with your wiring that needs immediate attention. I don't think that you want to create the false impression that our amps, improperly biased, could destroy your home.

4) The M60 does a marvelous job of driving 4-ohm speakers when coupled with Paul Speltz's Zero autoformers. This is a great device that "fixes low impedance speakers" -- that makes their load more amp friendly. It also has no sonic signature.

5) It is obvious that you weren't too keen on having to use the MP3 from the get go. My feeling is since it has no bearing on the MA1 review or the MA1's performance ( in fact to you the the MA1 sounded better with your own gear) there is no reason to trash the MP3. It should just not be mentioned. If you want to do a rigorous review of it in the future, we can arrange for that.

Harry Blazer

Manufacturer's website