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A tone-tweaker's dream head, now designed to sit comfortably on a 2x12" speaker cabinet.
THD put a BiValve-30 in the Head Box to give the BiValve-30 Box Head a more traditional guitar amp head look. The vinyl-covered Baltic birch ply cabinet gives the THD BiValve-30 Box Head a classic look and provides superior protection for the knobs and switches, both front and back. This Box Head version is designed to fit perfectly on top of THD's popular 2x12" speaker cabinet, but will be equally at home on any of the popular 2x12" or 4x12" cabinets on the market.
THD BiValve-30 30W Class A Amplifier Head
The THD BiValve-30 30W Class A Amplifier Head is a pure Class A design with 2 output tubes wired in parallel and combined through a special output transformer to deliver up to 30W. It accepts almost any type of output or preamp tube without bias adjustment-even in combination-for an astonishingly wide range of tone available for nearly any style of guitar playing. The standard of construction is absolutely top-class, as you would expect for any handmade amplifier.
Inside, you'll find large transformers and hi-fi style internal baffle plates to cut down on hum, as well as the tube sockets. On its front panel is a pair of input jacks labeled More and Less, followed by a Cut switch (high-cut filter), Volume, Treble, Bass, and Attitude (driver tube response control). In the center is a light bulb that glows as the amp distorts with a small switch to turn it off, a control for the built-in Hot Plate (output attenuator), and a defeat switch for the Hot Plate.
