How to get 15V sym out of a 9V power supply

[Majestic12]

I'm building a ringmodulator effect pedal for the guitar player in my band. The circuit needs (+15)-0-(-15)V to run. Does anybody have a schematic for a DC-DC converter circuit that suitable ?

 

[abbey road d enfer]

First, you must decide if the circuit would work with +/- 9 V, that would save one converter.
Now you must know the current requirement. If it's only a few mA, you could use charge-pump, but I would think the current requirement is more about some tens of mA, so I would suggest you buy one og these ready-made potted converters that can be had for less than 5 bucks.