Tube Power Amp Reviews

At the end of Gramophone Dreams #46, I was lost in the pristine beauty of Decware's 25th Anniversary Zen Triode amplifier driving the DeVore Fidelity Orangutan O/93 speakers. That was an extremely enjoyable system, and I was hoping to keep it intact for another month. My plan was simply to morph into my long-postponed opus on tube rolling using the Zen Triode as well as Ampsandsound's Bigger Ben headphone and loudspeaker amp. Both are single-ended triode, no-feedback designs and therefore perfectly suited for tube-swapping comparisons.

I am not a fan of that amp designer who promoted his products by pointing a condescending finger while scolding audiophiles, like errant children, for preferring their records to sound "pleasant" rather than "accurate."

He reminds me of my least favorite teacher, Professor Grausamkeit, who was just like that and said similar things. Every time I smarted back, "Accurate to what?" he'd whack me with a wooden yardstick.

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.

This, our February issue, is the first Stereophile issue to arrive during the year 2020, which marks the 50th anniversary of the founding of Audio Research—in my view one of the key events in the history of high-end audio. So it makes sense for this issue to include an Audio Research review—in this case, of the $20,000 Reference 160 S stereo amplifier.

Products come and go. Some impress more than others, and in our little world, the ones that impress the most wind up in Class A of our semiannual "Recommended Components" feature.

After a product makes it to that list, if Stereophile's reviewers go more than a few years without hearing it again—in a home system or a dealer's showroom or even at an audio show—that product falls off the list, usually quietly. Thus, if a reviewer is maximally knocked out by a piece of playback gear, yet the fates allow neither a purchase nor an extended loan, he or she or someone else on staff must endeavor to borrow it again so it can stay recommended.

I will never forget.

In 1988 I had my first experience with Western Electric 300B tubes. It took place on a quiet, streetlights-and-snow night at my friend Ryoichi's apartment on Riverside Drive, in Manhattan.

I had never heard of the late Japanese amplifier designer Ken Shindo, of Shindo Laboratory. But that evening, Ryo's audio system was all Shindo: a hammertone gray Shindo-restored, grease-bearing Garrard 301 turntable sitting on a Shindo plinth of glossy wood, with a Shindo-modified Ortofon tonearm and SPU cartridge, a Shindo moving-coil step-up transformer, and a Shindo preamplifier with a moving-magnet phono stage.

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?