Octaver-Fuzz build report

[jmusser]

I built this Thursday night, and got fire it up briefly yesterday. Here's the schematic: http://www.harpamps.com/schematics/geuoctv.pdf  This effect didn't come with a volume control, so I will include Mark Hammer's mod post for it: http://www.diystompboxes.com/smfforum/index.php?topic=38019.0  This is a fuzz, with an up octave option "struzz" switch. This uses two 9V batteries for a power supply with the dual op amp referenced at ground. You will note that the power pin is at +9V, and the normal ground pin, is at -9V. I figured with that type of amplitude it would have to be a screamer, and it was! Per Marks instructions, a volume control was added for the fuzz side, and the struzz side. The Fuzz side has an intense fuzz that is really nice and thick with the 1Meg Gain control maxed. As the Gain is lessened, the fuzz is less intense, and gets more bassy, though nothing that would be considered Big Muff like. Switch to "struzz", and you get a nice up octave fuzz. With the gain down, and guitar pick up in the bridge position, the octave is as close very clean sounding. Back the up octave volume off until just before it shuts off, and you get a lot of the sonic weirdness of ring modulation sounds (intermodulation distortion) on the bottom 3 strings from the 10th fret on up. I used a JRC4558D dual op amp, and a 2N5089 for the transistor. Be sure and have your amp volume down, because this thing is LOUD! If you're in fuzz or struss, and can back the gain down, you've got pretty decent overdrive with this effect too. This up octave is not as high pitched and deafening as say the Bobtavia, Simple Octave Up or NeOctavia, and reminds more of the "Blue on Black" tone that Kenny Wayne Shepard gets. I like the tone of it real well.