TAS Legacy: The Vendetta Research SCP-2 Phonostage

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TAS Legacy: The Vendetta Research SCP-2 Phonostage

With a price of $1895, the Vendetta Research SCP-2 was the most expensive phonostage on the market in 1988. Nonetheless, John Curl’s magnum opus was in demand for its unrivaled sound quality and low noise, and even today it is rare to see one on the used market.

The SCP-2 was a four-box affair; the left and right channel power supplies and left and right channel audio circuits were each housed in their own small square chassis. A rack-mounting kit was available that held two chassis side-by-side for more convenient operation. The word “utilitarian” best describes the casework. The SCP-2 chassis was the antithesis of the thick, engraved faceplates and lavish metalwork adorning some products of the era. There were no lights, buttons, switches, or controls—not even a power-indicator LED.

The standard version provided 62dB of gain, but a high-gain version (71dB) was available by request. Despite the absence of a step-up transformer at the input, the SCP-2 was astonishingly quiet, with a signal-to-noise ratio of 90dB (at 3V output). That’s far quieter than any previous phonostage, and a benchmark to which today’s phonostage designers still aspire. One of the secrets to the SCP-2B’s low noise was Curl’s selection of the input-stage FETs. Curl hand-measured each candidate FET with an analyzer that showed not just the FET’s intrinsic noise level, but also the spectrum of that noise. Selecting low-noise FETs isn’t unusual, but selecting on the basis of the noise’s spectral content was unprecedented, and reflects Curl’s uncompromising ethos. Incidentally, those FETs are no longer available, nor are any replacements that are as quiet. Cartridge loading was realized (10 ohms to 200 ohms) by adjusting a small trim-pot inconveniently located inside the chassis, and also inconveniently, with no calibration indicators around the trim-pot.

The direct-coupled circuit had a bandwidth of 1MHz, signal-to-noise ratio of 90dB, and less than 0.01 percent THD and IM. RIAA equalization was performed in two stages—the high-frequency roll-off passively in the first stage, and the low-frequency boost achieved in the feedback loop around the second stage.

My memories of the SCP-2—I had one in my system for about five years (1991–1996)—are dominated by its absolutely silent backgrounds. This lack of background noise allowed low-level details to emerge, enhancing the phonostage’s already high resolution. Dynamics were exceptionally wide, with a remarkable sense of speed and agility.

Even after more than 20 years, I can still recall the impression the SCP-2 made of hearing through the phonostage back to the source. The SCP-2B made every other phonostage I auditioned during those five years sound opaque, colored, veiled, and murky. I suspect that even by today’s standards, the SCP-2, particularly with all the updates, would still be a contender for the state of the art.