VTL MB750 monoblock power amplifier Page 3

The Leinsdorf/Boston reading of Bartok's Concerto for Orchestra (RCA LSC-2643) is another good example. This recording does a beautiful job of capturing the orchestra's huge size and layout within the ambient environment of Symphony Hall. A lot of amplifiers can pull this off at the softer end of the scale, but with the 750s, the perspective and soundstage held up even through the massive crescendos. The music simply swelled, without any hint of congestion or even the slightest flattening of the soundstage.

The dynamic punch and precision paid dividends on small-scale works as well. The initial jump when a bow touches viola or cello strings, for example, is the sort of microdynamic detail that adds a surprising amount to a recording's feel, its realism. Late one night I rediscovered a recording I hadn't listened to in quite some time: the Juilliard Quartet's reading of Beethoven's String Quartet 14 in c#, Op.131 (RSC LSC-2626). I've always liked the music, but had never thought this a particularly good recording until hearing it with the MB-750s in the system. The difference was the VTL's magical reproduction of microdynamic details.

And rock'n'roll, wow! If an amplifier can't cut it, the drum set near the opening of AC/DC's "You Shook Me All Night Long," from Back in Black (ATCO 98418-2), comes off sounding flat, more like a cardboard box than a drum set. With the 750s it wasn't just a drum set, but one with dimensionality—for that matter, one recorded in a very distinct acoustic space. Similarly, Rickie Lee Jones's cover of "Under the Boardwalk," from Girl at Her Volcano (Warner Bros. 23805-1), works only if the chops are sharp and punchy. With the VTLs they weren't merely punctuated, they exploded out of the silence. Score one for power.

Low-bass extension and impact is another area where power is expected to pay major dividends, and with the MB-750s, it certainly did. What's more, the bottom end was the one area where I preferred the tetrode mode. From the midrange up I preferred the triode mode, tetrode being slightly harsher and edgier, and with both the soundstage and individual images more two-dimensional. But on the bottom—120Hz on down with the Dvoraks—switching to tetrode improved control. Bass notes started and stopped more precisely, and there was a leaner, more natural balance between a note's fundamental and harmonics than was the case in triode. If anything, the MB-750s betrayed their thermionic origins in this particular characteristic, erring—if at all—on the side of a slightly too-lush harmonic structure. Timpani, for example, had a balance between the initial impact and characteristic round, rising harmonic structure that was tipped slightly in favor of the latter. All in all, though, no complaints. If I can have the detail, control, and power, I'll take a bit of extra richness over a threadbare harmonic structure any day.

In either mode there was little to complain about regarding the VTL's bottom end. My systems won't let me vouch for the bottom octave, but from 30Hz on up the VTLs were superb—not "superb for a tube amp," but superb, period. One great test of low-bass extension and resolution is the Mehta/Los Angeles reading of Holst's The Planets (London CS 6734, LP). When the double basses enter at the opening of "Saturn," the MB-750s gave them the appropriate weight and made it clear that there are several distinct instruments playing in unison, lined up in a row.

The MB-750s were absolutely killer on standup bass as well. On the Ray Brown Trio's Soular Energy (Concord Jazz LELP 111050), the 750s absolutely delighted me, capturing all the subtleties that make Brown's playing so distinctive, and beautifully balancing his fingering details and string snaps with the growl and resonance of his bass's body. The instrument's apparent size and weight grew naturally as the pitch descended, but never at the expense of detail or a consistent tonal character.

The bottom line on the bottom end is that, particularly when run in tetrode mode, the MB-750s delivered the slam and, more important, the control that I'd hope for with a super-power amplifier. They went well beyond just slam, though, giving bass instruments a realistic dimensionality, character, and warmth that you don't often hear outside of a concert hall or jazz club.

Okay, so the 750s delivered the raw power you'd expect from 750W. What about the downside? Are the big VTLs simply a crude, brute-force device—a chainsaw when a scalpel is what's really called for?

Not hardly. In fact, the MB-750s not only dispelled this thinking, they made it seem almost counterintuitive. Think about it. If it's the MB-750's outrageous power that allows a speaker to track a transient's leading edge precisely and accurately—even at the bottom end, where vast current reserves are required—won't that power similarly allow a speaker to follow all the nuances and subtleties of a musical signal? Obviously, the equation is more complicated than that and involves a host of engineering considerations, but it's going to be a lot easier if you've got enough voltage and current to do the job.

The reality was that the MB-750s did reproduce musical nuance and detail very well, and in a way that was consistent with live music and avoided the excesses of a lot of gear. For starters, they didn't draw attention to the low-level "chair-squeaking" type of microdetail. Those details were there—as I confirmed by switching between the MB-750s and an amp that several listeners had branded as "pristine" and "exquisitely detailed"—they were just painted with a slightly broader brush, and were less distinct from the background. A example from my notes was Buddy Rich's Big Swing Face (Pacific Jazz KN 10090), where, with the MB-750s, I was captivated by the "good club feel" rather than noticing the individual glasses clinking and the locations of their tables.

I can hear the cries now: "But, but, but..." Yes, the detail is undeniably in the recording, and no, the VTLs aren't as clear and crisp in their reproduction of that low-level detail as the best amps (in this regard) that I've heard. What I find more significant, though, is that the VTLs' low-level detail resolution more nearly approximated what I hear when I'm listening to live music.