The BSM HS model is based on the short-lived early edition British HORNBY-SKEWES unit produced, as used by Ritchie Blackmore, the brilliant and impulsive guitarist of Deep Purple. The unit produces a powerful and biting sound that was used to help create the epochal masterpieces e.g. "Deep Purple In Rock" and "Fireball". The long yearned for new edition, now issued under the name HS from BSM, includes the same germanium transistors as the 1965 version. The HS-Custom model includes a volume control (like Blackmore's modification).

Demo by  Brett Kingman

Demo by Manuel Bastian

Manual

Product Page

HS-Custom Treble Booster

BSM decided to take the idea of this classic Rock sound and came up with a completely different solution to hit the target. Not interested in making a simple copy of the circuit but developing own ideas to realize the functions with silicon transistors. What you get now is a flexible high gain treblebooster/preamp combination optimized for medium humbucker pickups that works also very well with P90s and singlecoils. It is intended to hit the high treble input of a British Plexi-type amp (or other classic British oriented tube amps) hard. What came out is a real monster, working at 18 volts. But we have to admit that it still works very well with 9 volts, just a little less monstrous. It also comes with a status LED. The preamp stage is a mild treblebooster of low noise followed by a high gain silicon output stage that can easily be symmetrically driven into saturation.

Demo by Haiko Heinz

Demo by EytschPi42

Black Box Booster

The BSM RM model is based on the British Range Master unit produced between 1965 and 1969, as used by Eric Clapton in John Mayall's Bluesbreakers. Eric also used the booster when playing in the legendary group Cream. Its biting, powerful sound is clearly in evidence on the Bluesbreakers "Beano" album. Blues rocker Rory Gallagher, Heavy Rock pioneer Tony Iommi and Brian May from Queen were also heavy users of the orginal Range Master unit. The Range Master unit was also used by G. Tipton & K.K. Downing of the British heavy metal band Judas Priest in the late 1970s years to push its amps in full-tilt heaven. The long yearned for new edition, now issued under the name RM from BSM, includes the same OC44 germanium transistors as the the original 1965 version.

Demo by Benedikt Schlereth

Demo by  Fretboard Playground

Review by guitartest.de

RM Treble Booster 

The BSM RM-Metal model is based on the British Range Master unit produced between 1965 and 1969, as used by Eric Clapton in John Mayall's Bluesbreakers. Eric also used the booster when playing in the legendary group Cream. Its biting, powerful sound is clearly in evidence on the Bluesbreakers "Beano" album. Blues rocker Rory Gallagher, Heavy Rock pioneer Tony Iommi and Brian May from Queen were also heavy users of the orginal Range Master unit. The long yearned for new edition, now issued under the name RM from BSM, includes the same OC44 germanium transistors as the the original 1965 version. The RM Metal is a modified '69er RM model like Mr. Iommi's unit, which he has used on his second Black Sabbath records and later. The RM Metal model is recommed for Nu-Rock, low dropped tunings and baritone guitars.

RM Metal Treble Booster

Review by Gitarre & Bass