THD UNIVALVE INSTRUCTION MANUAL
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THD UniValve
Instruction Manual
Thank you for your purchase of the THD UniValve amplifier! The THD UniValve is a
Single-Ended Class-A amplifier head with a single output tube that can be switched at
will among many octal-based power tubes, including 6L6, EL-34, 6550, 6CA7, 6V6,
6K6, KT-90, KT-88, KT-77 and KT-66, for different tones without re-biasing the amp.
Likewise, the two preamp tubes can be any combination of 12AX7, 12AT7, 12AU7,
12AY7 or 12AZ7. The UniValve delivers tones from smooth and clear to very aggressive
overdrive. It is easily capable of driving a 4x12" cabinet, yet quite small and light.
Finally, it has a built-in Hot Plate® Power Attenuator that allows for full output
distortion at almost any volume. The unique combination of our touch-sensitive input
circuit and the wonderfully active and reactive tone control section (that we slaved a year
to perfect) make for a front-end that really responds to subtle and not-so-subtle changes
in the signal being fed into the amplifier either by the guitar or any effect that may be
between the guitar and the amplifier.