Mark Levinson No.23.5 power amplifier Page 2

In both its construction and its design, the No.23.5 is a thoroughly modern amplifier, engineered for excellent sonics and long-term reliability (though it is a little more complicated than Commander Harrison's definition).

The No.23.5 served as one of the workhorse amplifiers during my last six months' worth of equipment reviews. As seems to be the fate of review samples, however, the No.23.5 suffered a fault in one channel a few weeks after delivery. An increase in distortion at low levels turned out to be due to a loose washer lodging itself where it could do most damage, something one would expect to be a one-off problem. A trip back to the factory put things right, and auditioning continued.

The original No.23 was not one of my favorite amplifiers. Powerful, yes; dynamic, very; but it had a vivid, upfront character in the low mid-treble that both presented the listener with very much of an in-the-orchestra balance and made system matching somewhat problematic if any of the other components had any kind of midrange forwardness. By contrast, the 23.5 is considerably more laid-back in this region, to the benefit of the music, which is, overall, less pushed forward at the listener.

This is not to say that it is a soft-sounding amplifier. Though the No.23.5 gets what J. Gordon Holt once called the "blatty brassiness" of trombones and French horns correct, its midrange is still rather forward and rather hard-sounding in absolute terms, meaning that it would be a less-than-optimum match for similarly balanced loudspeakers. I also occasionally detected what I thought was a hint of tizziness in the extreme highs, but not to any musically significant extent. The 23.5 is also unkind to hyped-up recordings. I was browsing in a mall record store while my wife hunted for baby things when I heard this strange mix of generic Eurosynth coupled with what sounded like Gregorian chant floating from the ceiling-mounted B&Ws.

"What's that?" I asked the assistant.


OK, I sprang for the $12.99 for Enigma's MCMXC a.D. (Charisma 2-91642). Why not? I'd go mall-crazy if I didn't buy something.

Why not became obvious when I got home. This recording has so much presence energy wound in by the engineers that it whistles. And the chant voices sound like the "before" example in an ad for a magic substance guar-an-teed to eliminate intermodulation distortion. The Levinson-driven WATTs let you hear every little thing the engineers had done—and it is not magic!

But it was in the bass where this Mark Levinson amplifier excelled. My listening notes keep coming back to the word "slam." No matter what speakers were hooked up to the No.23.5, the sound had a combination of low-frequency weight and extension that, in the loudest passages, felt like it would implode the listener's chest cavity. Even with the keyboard bass "drum" on the Enigma disc. I've mentioned track 3 of Jeff Beck's 1989 Guitar Shop album (Epic EK-44313), "Behind the Veil," in previous reviews. Drummer Terry Bozzio supplies a "real" backbeat bass drum that can literally explode into the listening room twice every measure. The Levinson gave this drum the appropriate weight, coupled with a dynamic solidity that maximally underpinned the music. On "Melody," track 2 of David Crosby's post-drug, post-prison Oh Yes I Can album (A&M CD 75021-5232-2), the synth underlying the song's bridge positively plunged in the bass, raising the listener's hackles almost as much as the velvet-edged, parallel-moving tenor harmonies that The Cros adds at the same time (footnote 2).

The word "dynamics" doesn't just apply to how loud a component will play without strain, though that is not an insignificant factor when it comes to musical enjoyment (at least for those of us not too staid to reach for our air guitars when the occasion permits—no, demands it). "Dynamics" perhaps more importantly describes how well a system reproduces the music's ebb and flow. With a truly Class A system—and in real life—there seems no limit to the manner in which the sounds of instruments can rise and diminish in volume. Neither does one instrument's sound modulate that of another. With less-than-perfect reproduced music, however, instruments and voices often seem to merge as they play louder. Rarely does the reproduced soundstage expand to encompass the listener—the sound just gets louder and more homogenized. The Mark Levinson more closely approaches the live situation in that the soundstage gets "bigger" as it gets louder, with an excellent sense of dynamic freedom.

A diagnostic recording I use in this respect is one I made some years back of Elgar's Dream of Gerontius. A massive work, scored for three solo voices, full orchestra, double choir, and organ, its quietest passages demand exceptional reproduction of detail to be rendered cleanly, with the appropriate image depth, while its climaxes stretch systems to, even past, their limits. Elgar often reinforced/exaggerated choral crescendi in this work by progressively adding instruments so that the overall sound gets both louder and more complex as it swells. More so than any other amplifier I have used, the Levinson faithfully tracked Gerontius's dynamic demands, both giving the impression of unlimited power reserves and doing an excellent job of keeping the individual sounds of instruments and voices suitably separate in these crescendi.

It is perhaps in its presentation of image depth where the No.23.5 doesn't quite scale the heights. Due to a lack of cooperation from the Ely Cathedral staff, the only place I was allowed to put the Soundfield microphone to record Gerontius was on a high stand above the conductor's head. This lends the recorded soundstage very much of a wide-angle perspective, the sense of depth being exaggerated compared to the real thing. Though the choir was behind the orchestra, the mike placement means that they sound quite a bit more distant than they were. The Levinson driving the WATT/Puppies brought them more forward, a case of two wrongs somewhat canceling.

One of the tracks I intend to put on the second Stereophile Test CD is a piece by Corey Greenberg, "Eden," where he uses all the possible tone colors that the Fender Stratocaster guitar is capable of to paint, via a multitrack recorder, a vividly defined yet totally artificial soundstage, extending from speaker to speaker and from the plane of the speakers to some point deep behind that plane. I say "artificial" because this soundstage does not correspond to any original event or to any real acoustic, yet the space between and behind the loudspeakers is illuminated by swirling and swooping, whammy-barred, fuzzed and phased, reverberated and repeat-echoed Strats overlaying a clean-machine cadential ostinato eerily reminiscent of Hendrix (to whom the piece is dedicated) performing "Angel" on the Lifelines set. Via the 23.5, this produced space (I can hardly say reproduced) is reverberant but with the rear walls of the space not particularly deep. The reverberation tails are clearly delineated by the 23.5, but the artificial space is not that large. Via a space-champ amp such as the Audio Research Classic 60, that acoustic sounds softer-walled, the ambient die-away being less well defined, but, paradoxically perhaps, it is considerably larger, the rear and side walls being set farther back from the listener.

Footnote 2: Richard Lehnert loaned me this CD just after I finished reading Crosby's biography, Long Time Gone, which, much to my surprise, I found both to be a moving book and one that brought into question my own attitude to so-called "recreational" drugs.
Harman Specialty Group
3 Oak Park Drive
Bedford, MA 01730-1413
(781) 280-0300