viva Analog “Octave Amp” // jcm(c)2009

High-Accuracy FW Rectifier

Inspired by the underlying operation of the Danelectro “Green Ringer” and Roger Mayer “Octavio”, this circuit takes the frequency doubling experience to new heights …

It features a high-voltage circuit capable of producing highly symmetric Full-Wave rectification – in the process voiding the fundamental near completely.

This circuit tests out what happens when the two lobes that form a double frequency waveform bend are perfectly matched … unlike single-ended PI circuits and transformer based FW rectifiers this one produces ultra high octave-to-fundamental ratios … to the point where the characteristic “ring” that one gets when playing double-stops (try a tri-tone!) goes beyond any other analogue circuit … this is for guitar players seeking a new version of the well-known effect, on bass it gives a very unique ringy fuzz which retains good bottom – more than your usual fuzz box, on Fender Rhodes it’s insane …

the switching circuit also features a new version of a constant-current LED switching circuit, providing (i) zero switch pop and (ii) adjustable bypass LED brightness (anything from off, low or full on) …

check out the “Octave Amp” in action here (*!*):