dual power supply effects?

[drewl]

Are there any pedals that run off a 9v battery that use a plus and minus power supply?
I have some preamps from a dead mixer that use a positive and negative voltage that I've got some twisted ideas for.
If I look at some pedals with a dual supply and can steal some ideas on setting up the power supply to save time messing around, thanks.

[morcey2]

The GGG version of the geofex ABY box.

http://www.generalguitargadgets.com/pdf/ggg_amp_aby.pdf

It uses a charge pump to get the -9-ish volts.  That's the first one that comes to mind.

Matt

[Ben N]

Most of Craig Anderton's effects in EPFM and his GP column were designed to run on +/-9v, using two batteries or a bipolar supply, which he also provided a DIY design for. Some could probably be reworked for voltage divider Vr operation, but I guess the modern solution is the charge pump.

[drewl]

Thanks!

I could use 2 9v's, but thats too easy.
Anyway, I have a bunch of tiny surface mount preamps from a dead mixer, 2 amps on each board each with 2 inputs (dual 4560's with input buffers!) from what would be the XLR inputs.
They will run from +/- 4.5v so I was hoping to get away with a single battery.
After figuring out what all the pin connections are, with ~100mv input I can get up to 3v out where it starts clipping.
a 10 to 25k pot between two of the pins varies the gain.
I'm thinking a couple switchable diodes on the output and voila' I've a got a dual preamp/distortion pedal.

I can't stress enough the value of finding/buying/stealing dead mixers for parts and pieces. I've gotten like 30 real nice 1/4" enclosed switching jacks from this thing, tons of small pots, knobs and all kinds of parts!

[moosapotamus]

They will run from +/- 4.5v so I was hoping to get away with a single battery.

I would guess that you could use a single 9v battery if you wire the pos battery terminal to V+, the neg battery terminal to V-, and the standard Vbias type resistor divider arrangement going to the ground, or 0V points.

~ Charlie