Audio by Van Alstine Transcendence Eight Preamplifier

Equipment report
Tubed power amplifiers
Van Alstine Transcendence Eight
Audio by Van Alstine Transcendence Eight Preamplifier

I like this product’s name, and not just because of its promise of reaching beyond the common range of perception. It’s the version number—the Eight—that really piqued my interest, suggesting a mature product evolved through multiple design iterations. Selling direct, as AVA does, helps to keep prices down, but to extract good sound on a budget it is essential for the designer to put his ears into the design loop, critically evaluating component and circuit options, as there is only so much money you can throw at a given project. And this is something Frank Van Alstine has done for over 35 years, judging by the success of his numerous modifications of vintage gear. Extracting maximum bang for the buck is apparently a way of life at AVA. Frank tells me that his goal is to “build as high a quality and durable a piece as possible, while trying to keep prices in the range affordable by mortals.” Somehow he still manages to include gold-plated switch-contacts and jacks, precision controls, and power-supply regulation.

Functionally, the Transcendence Eight (T8) is a mixture of old-fashioned and standard features and is intended to serve as a full-function preamplifier, rather than as a bare-bones linestage. In addition to the obligatory volume pot and inputselector switch, there’s a balance control, mono-mode selector (useful for playback of single-channel sources and noisy FM stations), two tape loops, and a headphone jack. Three AC convenience outlets are located on the rear panel. The headphone driver is built around a fast integrated chip configured as a unity-gain buffer, offering low output impedance and high current drive. While I made no attempt to evaluate the headphone driver in depth, a quick listen via my Grado RS-1 cans indicated more than sufficient drive, but a sonic flavor more akin to solidstate than tubes. An optional phonostage is available, as is a motor-driven remote volume control. And that’s how my review sample was outfitted, bringing the price tag to $1697.

Van Alstine was forthcoming in providing me with a schematic of the T8. He warned me that there wasn’t that much amazing to look at and that the magic is “pretty much just good execution and careful calculation of circuit time constants to insure outstanding stability and bandwidth.” The truth is that there’s nothing revolutionary left to do in tube audio. It was already a mature technology in the 1960s, and much of what passes for new today is nothing more than a rehashing of vintage technology. (In fact, did anyone notice that the vacuum tube celebrated its 100th anniversary last year?)

The line-level input stage is built around a “plain vanilla” grounded cathode circuit. A single Russian 6N1P dualtriode is used per channel. This mediumtransconductance, low-distortion tube is, with the exception of higher heater-current consumption, a direct replacement for 6DJ8/6922 types. The triode sections are cascaded to give plenty of voltage gain— more, in fact than I could ever imagine being necessary for CD line-level inputs. There is no cathode-follower stage, which means that the line output impedance is fairly high—a bad thing when driving low-input-impedance power amps. The RIAA phonostage topology is similar and is based on a single 12AX7 dual-triode per channel. The power supply is solid-state and fully regulated. No global feedback is used. One of AVA’s “secrets” is the use of separate highvoltage regulators for each triode section; for the two 6N1P tubes in the linestage and two 12AX7 in the phonostage that’s a total of eight regulators in all! And these are zener-controlled, high-voltage power MOSFETs. A replacement tube set of selected and matched phono and line tubes is offered at reasonable cost ($29).

It is rare for a sub-$2k preamplifier (the T8 base price is $1099) to compete in one or more performance aspects with the best money can buy. But with digital source material, the line section amazed me in several important aspects First and foremost, the music’s tension was reproduced fully intact. That is to say that the T8 was never a dull, boring little fellow. Polite, sterile sound is what I find most off-putting about most solidstate linestages (though there are happy exceptions), and the T8 offered a potent antidote. The music’s grandeur and drama were fully drawn out. Its ability to engage the highest gear, to rev up explosively from soft to loud, was impressive. Familiar vocals were given free reign, from a soft whisper to full shout. The T8 didn’t seem to know about compression. The impression of speed was enhanced by excellent transient attack, and controlled decay enabled the silence between notes to be clearly perceived.

Image outlines were tightly focused within a deep soundstage and fleshed out with palpable presence. This level of performance, long an area of tube supremacy, was of course dependent on the associated amplifier. To its credit, the T8 was good enough to keep up with the imaging prowess of the single-ended deHavilland GM70 tube amp.

Tonal character was also unchanged with a variety of program material, being consistently close to neutral in presentation. The bass range was neither ripe nor lean. The upper octaves were well extended and lacking the harmonic brightness that some mistake for genuine detail and presence. This was a good thing in my book, as there are already plenty of bright-sounding speakers out there. However, and this is the proverbial fly in the ointment, the treble lacked a measure of delicacy. It’s fair to say that the T8 did not sound like a vintage tube preamp, but more like a hybrid. It lacked the harmonic warmth and liquidity that characterize romantic tube sound. Midrange textures were slightly grainy in nature. OK, nothing gross, but discernible, nonetheless. If velvet were assigned a perfect 10 and sandpaper a 1 on a scale of 1 to 10, then the T8 linestage would earn a respectable 7. Harmonic colors were a bit bleached out relative to the real thing. It is important to point out that when matched to a romantic-sounding power amplifier, the T8’s linestage shortcomings were easy to overlook.

I was less enthusiastic about the RIAA phonostage. Out of the box it didn’t prove to be the quietest gain stage on the planet. The overall noise floor was considerably elevated—a bothersome issue with high-sensitivity speakers. Now comes the spooky part. As if he had read my mind, Frank Van Alstine e-mails me to say that the grounding scheme of the T8 has been improved by simply moving the main grounding wire closer to the first main power-supply capacitor, cutting the linestage background noise in half (from 4–5mV to 2mV broadband). Back went my sample to the factory. It returned with a note stating that the linestage noise level was now around 1mV broadband. That certainly did take care of the noise issue.

There was more than enough gain to be had—at least for the movingmagnet cartridges this stage is designed for. Running my Grado Reference mm cartridge directly in, at a VTF of 1.7 gram, allowed the T8’s strong virtues to shine through. Its unmistakable cornerstone of quick attack, dynamics, and spatiality was very much in evidence. But it seemed that its relative flaws in the treble and midrange were exaggerated. Not only were textures grainier to the ear, but brass assumed a slightly more brittle character. As a sanity check, and to put matters into perspective, I decided to pit the T8 phonostage directly against the Air Tight ATE-2, the latter being a much more expensive tube-rectified design known for its distinctly vintage sound. It was thus possible to bypass the T8’s built-in phonostage. I like the ATE-2 very much, and when servicing the Grado Reference its exemplary liquidity and textural smoothness provided a perfect backdrop for judging the T8’s performance. While the ATE-2 rewarded me with silky smooth highs, the T8’s phonostage shortcomings were brought into focus. The final diagnosis: a touch of overly sibilant and brittle upper registers.