discussion about gain and powe supply for an amp

[scaesic]

I've put together a first stab at an amp design.

This uses jack ormans mosfet boost into a tonestack into a TDA2050 power amp.

I've intially decided to use +/-15V split rails (as the tnoe stack is designed for that), with the mosfet boost using just +15V.

This will mean the TDA2050 is running on about 30V (as apposed to the 50V specified in the spec sheet),

My question is: At these voltages does the max gain through the circuit seem about right for a single coiled guitar?

Are these power voltages sensible and easily achievable? (ideally i'd like to use a cots power supply pcb, ideally looking for a PCB off the shelf with something that provides -20V, -15V, 0V, +15V, +20V, and i'm estimating this thing is going to suck up of the order of 1amp of current)

Schematic is here: Imageshack - parkmod.jpg