Treble booster

A treble booster is an effects unit used by guitarists to increase the high end of their tonal spectrum.

Vox even decreased the output of the American made version of their treble booster because they were afraid that the signal would overload the amplifier's input stage.

Popularized by guitarists such as Tony Iommi,[2] Ritchie Blackmore, Rory Gallagher, Brian May, and Marc Bolan,[3][4] treble boosters were used to overdrive amplifiers (mostly dark sounding, British tube models such as Marshall Bluesbreakers and Vox AC30s) in order to create a more distorted yet focused sound.

The original Rangemaster was an important ingredient for Brian May, Tony Iommi, Billy Gibbons, Marc Bolan or Rory Gallagher in finding their personal signature sound.

Later some of these artists switched to close derivative circuits or tweaked clones - Tony Iommi's Rangemaster for example was modified to be full-range.

[13] The Colorsound Power Boost is a treble and bass booster that runs on 18 volts, using two nine-volt batteries.