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With again chunky metal work for the now 25lb enclosure plus a solid remote wand, the fully loaded StereoKnight TVC is a luxurious affair overshadowed in only one functionality aspect by the now discontinued Bent Audio Tap-X with its twice-as-many steps; and the forthcoming $12.000 Audience Wavemaster at right. That will be based on custom Ohno-wired Bent Audio Slagleformers with an Audience-designed buffer circuit, headphone output and more. While the Wavemaster beats the StereoKnight on volume increments—61 over 33—it eliminates the 'cross-coupled' XLR sockets.


James Zhang's remote option does seem a true lifesaver for the passive preamp which as a breed often suffers hair-shirt puritanism. On functionality, his solution makes no apologies to modern expectations; except for not doing 0.5dB steps over a 60dB range. As mom tells little Willy at least once a week, "can't have everything".


The Silverstone appellation for StereoKnight's passive platform—available purely single-ended (RCA), balanced (RCA+XLR), with/without remote and with copper or silver iron—sends a passing nod at Serge Schmidlin's SilverRock as the perhaps grand daddy of the genre (today's Swiss version begins at CHF 8.600]. Schmidlin's support for TVCs is best explained by this quote: "One should keep in mind that a conventional 100KOhms potentiometer places a 50kOhms resistor in series with the signal when set at a medium position.


"With a 300pF cable or input capacitance, this situation leads to an attenuation of -3dB at 11kHz. The lower you go with the volume setting, the narrower the bandwidth becomes right in the audio band. One finally understands why at low levels our audio systems sound so bad. With a transformer potentiometer you get the opposite. The lower the volume is set, the lower the output impedance of your system becomes and the wider its bandwidth."

This neatly circumvents the known limitation of resistive passives to drive longer interconnects. It also means that to drive longer cables, a TVC should be run in the lower third of its range. This requires a source output voltage of sufficient potency for a given balance of room size, listening distance and desired average levels. If you run a TVC at close to unity gain, you'd probably be better off invoking very modest amounts of digital attenuation right at the source whilst foregoing additional wiring to the passive and inside of it.

Back to James Zhang. "Basically the copper version of the balanced Silverstone retails at $1.450 and the silver version at $2.000. Remote control (what we call the Silverstone B&R) adds $400 over the manual version." Meanwhile Samuel Furon of Ocellia had read my review on Yamamoto's volume controller and emailed the following:


"Since I began working in Canada and visiting clients in their homes, I have listened to many different systems which most the time weren't very good. In each of those situations one of the biggest problems was invariably the preamp. I explained to these folks that the use of a passive preamp would be the solution to improving their systems. So I was very happy to read about the Yamamoto passive preamp. It's exactly along the lines of what I've been thinking about for quite some time now."

  

StereoKnight's tube pre with TVC front end

Steve Klein of the Sounds of Silence dealership reported that "maybe add to your list of passive pres a unit called the Paeonia from Musical Laboratory. It's an incredible piece without many comfort features but sonically no negatives. I use it every day and have sold over a dozen without any complaints. In fact most customers have sold their $20.000 - $50.000 active units for this one. With high-efficiency speakers, this is a must hear (I reviewed it here two years ago)."

Aficionados of upscale valve amps and higher efficiency speakers were thus quite vocal about the particularly copasetic performance of passives in such contexts. My own experience with the Voxativ Ampeggio and Yamamoto controller certainly fell straight in line as did my subsequent search for the perfect mate for my Trafomatic Kaivalya monos. Unsolicited confirmation overlap seems quite indicative. There really is something to this hardware constellation. Now factor StereoKnight's attractive sell prices, clearly solid build and unexpected functionality. For the right people, this assignment had the makings of good tidings.
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