Audio Research Classic 60 power amplifier Page 3
Well, Gordon, old son, I'm afraid that I do hear that kind of precision live—given the equivalent conditions. When the recorded orchestra subtends an angle of some 60 degrees, it is not surprising that similar pinpoint imaging cannot be experienced by a listener sitting in front of the real thing far enough back in the concert hall so that the entire orchestra can be covered by his or her open hand. First, the angle subtended by the orchestra in this situation is about 10-15 degrees, and it is naïve to expect human hearing to increase its positional acuity when the listener is sitting farther back. Second, in a good concert hall, unless you're sitting in Row N or closer, you'll be hearing significantly more reflected sound than direct, particularly in a hall with a low ceiling, this again confusing the ear/brain. In a closer seat, so that the orchestra subtends an angle of 45-60 degrees, things are somewhat different.
With the exception of the French horns, which perversely take a delight in pointing the bells of their instruments at the back of the stage—Janacek's Sinfonietta being the only common exception that springs to mind—and the violins and cellos, which are generally spread in a large enough arc that you hear their sound coming from quite a large lateral angle, instrumental images can be pinpoint-sharp, depending on the concert hall. Many don't like this, finding it oppressive, but please don't tell me that it doesn't exist (footnote 2).
The relevance of this argument to my reviews is that when we recorded Stereophile's Poem album, we deliberately chose to use a microphone technique that captured the true, live, angular size of the piano and flute. Their images should sound quite narrow, therefore, compared with the total width of the stage between the loudspeakers. If you hear a wide piano, or a flute image that appears to move around the stage, then your system is doing something wrong, no matter how much you like the effect. The real-life images of the instrument were narrow; that should be the paradigm for accurate presentation of that recording's soundstage.
And with Audio Research's Classic 60, whether it was used to drive the Celestion SL700s or the Avalon Eclipses, that is what I heard. The pinpoint flute image was anchored in space, in front of a piano that occupied about one third of the distance between the loudspeakers. The rest of the stage was filled with the sound of the hall. Similarly with the London Sibelius recording mentioned earlier: via the Classic 60, instruments were firmly and unambiguously fixed in the recording acoustic. And rather than those images being presented as being flat, cartoon-like, they had that essential rounding to their outlines that suggested solidity, adding significantly to both the illusion and to the musical enjoyment.
This was noticeable even on recordings where there was no acoustic original. There was a satisfying solidity to the drum images on the Jeff Beck Guitar Shop album (Epic EK-44313); in fact, this whole album reproduced with an excellent sense of space, despite being a total studio production. Check out the soundstage layering on track 3, "Behind the Veil"—more of that backbeat bass drum—for an example of what I'm talking about: a wide, deep soundstage that reproduces via the Audio Research with oodles of detail.
Adding to the sense of verisimilitude with which the Classic 60 reproduced drums was its startling sense of dynamics, startling in that this is, after all, a relatively low-powered amplifier. It didn't lack for "jump factor." Several times during the auditioning I found myself caught by surprise as a loud peak came over as being louder and peakier than I had remembered. The bang accompanied by a finger cymbal halfway through track 4 on the Harmonia Mundi La Folia album (HM 90.1050), for example, or the whip cracks at 3:59 into track 8, never failed to make me jump out of my skin.
For "official" comparisons with the Mark Levinson No.20.5s, for which I used the SL700s, the levels of each amplifier were equalized at 1kHz using a Fluke 87 digital multimeter (DMM) (footnote 3). The Levinsons were driven in balanced mode using AudioQuest Lapis, while the ARC amplifier was driven in single-ended form with the Audio Research interconnect. (Sufficiently long lengths of unbalanced Lapis were not to hand during the review period.) This unfortunately adds an additional variable, one that in my experience renders the sound of the Levinson more reticent in the highs, more laid-back, than it actually is. However, a direct comparison with both amps warmed up confirmed my earlier statement that the solid-state amp has a rather more grainy upper treble, even though the AudioQuest cable lent its sound a rather closed-in balance compared with the tube amp.
Footnote 2: Please note, however, that I am not an advocate of '60s Columbia recordings, where the first violins were crowded into a telephone booth on far stage right, the cellos into a similar booth on far stage left. The Stravinsky/Craft recordings were the worst examples of this perversion.—John Atkinson
Footnote 3: This excellent, true-RMS handheld multimeter is superb value for around $250 (mail-order price), and has become an indispensable part of my listening room setup.—John Atkinson