Also a
guitar effect pedal first popularized by
Jimi Hendrix.
It can most clearly be heard on the guitar solo to "
Purple Haze," on the
LP "
Are You Experienced?"
Its characteristic sound is not unlike a
fuzz box, with the addition of a
note an
octave above the original note added to the signal. The octave effect is more pronounced when playing through a guitar's neck
pickup, with the
tone control rolled back to de-emphasize the treble.
Construction-wise, the pedal differs little from a
distortion or fuzz unit, with the addition of a step-up
transformer that causes the frequency doubling. There is usually a series of
diodes between the transformer and the
output jack, which serve to clip the
waveform and distort it.