Titan Boost/Ocrave – John Hollis

John Hollis Titan boost/octave. This is an op amp input pre amp/booster into a transformer. The transformer is 1k/20k and can output 30v from a 9v battery. The switch inserts a diode bridge for an octave effect.

The sound of the boost warm and clear. The octave effect is pretty good and different from other transformer based effects since the input signal is clean rather than a fuzz tone.

Ampeg Scrambler

Wired up this ampeg scrambler board I’ve had for a while. I’ve been trying to finish up all of the unfinished projects from the last few years.

Fired up first test. I used MPSA13 transistors. I got the PCB from John Lyons on DIYStompboxes. It’s the tone pad layout. The layout is set up for different transistor pin arrangements. The MPSA13s were working well, I was thinking to try some others before boxing this up.

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Octave Fuzz Take 2

Here’s an updated version of the octave fuzz. Q1 and Q2 set up a basic NPN Fuzz Face type circuit. While Q3 acts as a phase splitter. Q4 and Q5 act as a frequency doubler each side being fed an inverted signal from Q3.

So far the Fuzz section is working on the breadboard. The octave section is not working at the moment. I suspect the bias is off. Note the voltage around Q3. The collector and emitter voltages should be close to 4.5V. So far they are pretty far off.