The original black box, directly descended from Ken Schaffer's legendary SVDS, advanced forty years with 2017 engineering and manufacturing. Created as a 1:1 replica of the original Schaffer-Vega Diversity System audio circuitry, The Schaffer Replica has a unique boost and "bloom"- an indelible sound signature. This device brings back that elusive sound heard on albums such as AC/DC's Back in Black and Highway to Hell.

The phenomenon is also referred to as "warmth","fuller range","rounder, more dominant presence", "honk", or a "mid-range shift". While boosting the signal and enhancing even-ordered harmonics, the TSR creates lush, full, desirable tone, bringing the sound of the instrument out of the mix with clarity & prominence, while maintaining the full tonal character of the instrument.

This is our latest update: TSR4 (4.4) is all Colorado-built with evolved "SD 303" graphics, 12 & 15V compatible, enhanced circuitry w/ surge protection, launched Spring 2017. This classic TSR version is directly derived from our very first generation of the Schaffer Replica, the Gold Tag, which was and is still being used by many of the heaviest players in the industry, notably Angus Young himself on AC/DC's Rock or Bust album and tour. Guns n' Roses' Richard Fortus (close friend of Angus Young) is presently using the GT for the entire 2017 Guns n' Roses Not In This Lifetime Tour. Keith Urban, Pino Palladino, Keith Richards, Billie Joe Armstrong, Sting, Scott Metzger, Lettuce, Blackberry Smoke, The Biters, Airbourne, Isaiah Sharkey, and Coco Montoya are some of our active artists who use the TSR onstage and in the studio.

The circuit is 100% analog and features a compander (compressor-expander), which imbues your tone with extra sustain, fatness and a rich harmonic content. The newest TSR also features a very powerful pre-amp, capable of delivering up to 30db of clean boost.

The TSR4 Pedal is built using SMD components in order to achieve certain quality of tone within a more compact 159OB housing, while still retaining the same tonal footprint of the first Gold Tag units. TSR is housed in a durable custom enclosure and also features the exact same period-correct knobs used on the original SVDS in the 1970s.

Many players across many genres still love the stronger midrange offered by our 'classic' TSR circuitry. Our updates over the past 22 months have made the unit essentially bulletproof, more versatile, and far more resistant to power surges and polarity swaps.

There you have it - just as it was long ago, when we were starting in our small lab in Europe: the same focused dedication to tone, now handcrafted deep in the mountains of Colorado, USA with select-grade components.