Tube Power Amp Reviews

VAC's Statement 452 iQ Musicbloc amplifier ($75,000 for a single amp; $150,000/pair mono, as reviewed) is tall, young, and lovely, but unlike the girl from Ipanema, it isn't tan. Nor, at 280lb in its flight case, is it likely to "go walkin'." Getting the pair moved into my listening room required considerable effort—fortunately not mine.

We mentioned in the last issue that we were becoming increasingly disturbed by "a certain manic quality that is creeping into this pursuit of sonic perfection." We were referring then to a manufacturer's announcement of the imminent availability of a speaker system weighing over 1000 lb per channel, but we could just as well have been speaking of this behemoth from Audio Research.

To audio designers in Japan and elsewhere, the single-ended, 300B-tubed amplifier is like a haiku: an art form defined by both its prescribed limitations and the potential such restraint offers for artistic expression. Here, the only hard-and-fast rule is a simple one: output devices are limited to one 300B directly heated triode tube per channel. From there, it's a blank slate: Do you want AC or DC on the output-tube heaters? Tube or solid-state rectification? Low or high gain? Fixed or cathode bias? New parts, vintage parts, or a mix of both? Triode or pentode tubes as drivers? Capacitors or transformers—or nothing at all—between the plates of the driver tubes and the grids of the output tubes?