Now's the time to check the VPA's Load…
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Your quartet of "fitted" tubes should work fine right out of the box. I always gave the tubes a few minutes to come up to temperature before unmuting the amps with a flick of the function selector. On turn-on, the meters boogie about a bit as the electrons begin to flow, and quickly settle down to a nice, steady idle. When I shut them down to change cables or interconnects and then powered up again within a short time, the 845s lightly thumped the woofers with a brief, low-level transient—even while muted. Aside from that, they behaved beautifully.
Imaging was enhanced by another quality, one more difficult to describe. I've called it "inner light" before, some quality of openness and warmth in the upper midrange and treble that's especially evident with female vocals. I've heard it with 300Bs and good 6550s—like the Svetlanas. I've heard this inner light warmer and brighter with some other amplifiers—certain OTL amplifiers—and, on one memorable occasion, as a smoldering, almost hidden inner illumination. The big 845s had it too, but very slightly. It's just a suggestion, nothing too gross or pyrotechnic—just enough to put the blush in…
Re-creation of acoustic space was always a strong point of the VPAs. There can be no better example of this than Vlatko Stelanovski and Miroslav Tadic's Krushevo (M•A Recordings M044A). The guitarists play soulful duos inside a hemispherical structure called the Macedonian Monument in Krushevo, Macedonia—there are a lot of cultural harmonics, quite apart from those of the two guitars (footnote 3). You'll play this CD not for audiophile-approved pinpoint imaging (of which there is none), but for its fabulous music, the tonal color and sense of space, the reverberant bloom and lovely acoustic…
Sidebar 1: Specifications
Description: Vacuum-tube monoblock power amplifier with class-A push-pull output stage. Tube complement per chassis: one ECC82, one ECC83, two 845. Input: balanced on XLR only, pin 2 hot. Loudspeaker terminals: 4, 8, and 16 ohm taps. Maximum output power: 50W (17dBW) when load is matched to output transformer tap. Input sensitivity: 400mV for maximum power. Input impedance: 100k ohms.
Dimensions: 14¾" H by 4½" W by 13" D (without tubes/feet installed). Weight: 30 lbs each.
Serial numbers of units reviewed: 5520103, 5520104.
Price: $13,200/pair.…
Sidebar 2: Associated Equipment
When doing digital, I spun discs on the still-lovely-sounding Forsell Air Bearing CD transport. It sounded wonderful up on a trio of large PolyCrystal Cones on a pumped-up Bright Star Air Mass 2, itself atop a PolyCrystal equipment stand. Connecting to the dCS 972 D/D converter, I used both AES/EBU and BNC'd S/PDIF XLO The Limited datalinks. (They are so superb.) The upsampled 24/192 datastream fed the dCS Elgar via another pair of XLO The Limited datalinks for dual-AES running. (The Elgar can't lock to 192kHz on a single-AES connection.) I used the…
Sidebar 3: Measurements
The VPA was warmed up for approximately 15 minutes prior to any measurements being taken; according to Nagra, the amplifier should enter stable operation after this period. All measurements were made in balanced mode. The 8 ohm measurements were taken from the 8 ohm outputs, 4 and 2 ohm measurements from the 4 ohm outputs.
The Nagra's input impedance is too high (good) to measure accurately on our Audio Precision test set. The two voltages required to produce the measurement differed by mere thousandths of a volt. (With the slight variations in this range…
The affair started quietly enough, with the following exchange that appeared in Stereophile's January 2001 "Letters" section, following my decision to put the Digital Audio Labs CardDeluxe high-end PC soundcard on the cover of our September 2000 issue:
Where's the real magazine?
Editor: Could you please send me the real September 2000 Stereophile? I received Stereo Review instead. It's kind of puzzling, because it did say "Stereophile" on the cover, but inside it was definitely Stereo Review. I know because of the ads from Cambridge, Denon, Infinity, JVC, and Kenwood—you know, the…
Stereophile February 2001, Vol.24 No.2 / "As We See It"
By John Atkinson
By John Atkinson
Jonathan Scull told me there'd be trouble when I decided to put the Denon AVR-4800 surround receiver on our December cover. As you can see from this issue's "Letters," he was right. Although reader Bob Laurie and retailer John Weires refer to the AVR-4800 as a "home theater" component, Stereophile's review did examine the Denon's performance in the context of music reproduction. I suspect, therefore, that assuming these writers did read the review, their objection is really to the concept of surround sound, and…
Letters, March 2001, Vol.24 No.3
But the subject wasn't closed when the February 2001 issue hit the newsstands. The following letters were published in the March 2001 Stereophile, which in turn triggered that issue's "As We See It" essay.
A waste of space?
Editor: Okay, people—very funny. A DVD player gracing the cover of the November Stereophile and a receiver on the cover of the December issue?! What do you have in store for the January cover? A 100-disc changer? An Aiwa mini system? Ooh, ooh, I've got it—how about a Bose Wave Radio?!!
Oh, and be sure to waste…
Stereophile March 2001, Vol.24 No.3 / "As We See It"
By John Atkinson
By John Atkinson
"Jonathan Scull told me there'd be trouble when I decided to put the Denon AVR-4800 surround receiver on our December cover."
So began last month's "As We See It," written in response to letters of complaint that appeared in the same issue. Somewhat to my surprise, the negative letters are still coming in (see p.11). I conjectured last month that the real objection to our featuring the Denon in Stereophile was not that it was, per se, a home-theater component—we paid no editorial attention to how the…