Treble booster

A treble booster is an effects unit used by guitarists to boost volume and especially the high end of their tonal spectrum, and was popular mostly during the 1960s.

Popularized by guitarists such as Tony Iommi,Ritchie Blackmore, Rory Gallagher, Brian May, and Marc Bolan, 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. They came up in the mid-1960s. By the 1980s they had fallen out of use. Guitarists used overdrive pedals instead, in a similar fashion. But the circuit and its derivatives have experienced a great revival in the 21st century, thanks to the many boutique builders who have rediscovered the circuit. While IC-based overdrive pedals remain far more popular than treble boosters, some players prefer the less compressed and more dynamic response of Rangemaster-family boosters.

One of the earliest treble booster was the Dallas Rangemaster. Unlike most of today's clones, the original Rangemaster was not a pedal, but a box meant to be placed on top of the amplifier. The circuit makes use of a single OC71 or OC44 germanium transistor.

The Rangemaster has also been used extensively by Brian May, Tony Iommi, Marc Bolan and Rory Gallagher.

Just like the Dallas Rangemaster, the Hornby Skewes treble booster was an amp-top unit.

While early Hornby Skewes Treble Booster units used a germanium transistor, the later, better-known version features a silicon transistor. Rumours about a JFET version may source from a misread part number.

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