Roger Mayer is an electrical engineer who developed several electric guitar effects, including the Octavia, a fuzz effects pedal which also doubled signal frequency, with a sound that was not attainable by simply connecting an octave pedal and a fuzz pedal together. The effect was popularized by Jimi Hendrix, and can be heard during the solos on the song "Purple Haze".[1][2]
The Octavia, as well as several other effects, are still being produced under Roger Mayer's name.
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