True V+ and V- voltage doubler 9 to 18 Volts

[Sauerkret]

Hello,

I have the following question.
I am combining 2 effects together: A Wah based on the one found in the ADA MP-2 preamp and a Active Baxandall EQ.
The wah uses the OPA2604 (and 604) and needs 15-25 volts (I'm thinking 18V here) and the Baxandall EQ has a OPA2132 and runs on 9 Volts.
Both circuits need a true + and - source. I'll not be using a battery. Can't find anything that would work for me the closest thing is this.

But the 9volt side does not have a true V-.

Any help would be greatly appreciated.
Regards, Eric

[Sauerkret]

I'll swap the OPA2132 with the OPA2604 and run both on +18V and -18V

[stm]

I'm pretty sure you'll find your -9V at pin 5 of IC1 in the circuit above.

[PRR]

> the Baxandall EQ has a OPA2132 and runs on 9 Volts.

It can eat +/-18V just fine.

> need a true + and - source. I'll not be using a battery.

I'm not a big fan of taking hi-volt AC, to DC, to AC, to DC again. There's times to do such contraptions. But there are other ways.

A 9V-12V AC wall-wart, 2 diodes, 2 1,000uFd caps. This can give the voltages wanted for simple op-amp powering. It's probably on R.G.'s site. The ripple may be a bit much, and the DC voltage may be a bit close to the chip limits. Add two 220 ohm resistors and two more 1,000uFd caps, it will be clean enough for any good opamp.

You can probably plagiarize the whole PS from Rane or Ross schematics.