Yes, I know I'm all questions on the forum at the moment, but I'm a bit pressed trying to get a blues harp pedal sorted out for a mate and can't take my usual time (several years) to figure it out myself.
It looks like said pedal will have at least one module that requires a bipolar power supply and so I'm thinking about the advantage in clean headroom that would give to the Subcaster especially since high gain feedback seems to be a harp problem.
Unfortunately, I have no clue where to start.
I'm concerned that the heater draw if taken from the + side might skew the power supply. I'd thought to use an LT1054 or an ICL7660 (Max 1044-alike) to create the bipolar supply. That's just one of the issues though. I probably will ditch the LM317 and associated comps. to go with Rick/R.G.'s 18ohm 3 watt resistor to get 6.3V for the heater.
Anyway, if some kind soul could point the way I might have a crack at it, otherwise I'll make the 12V version, but it'll feel like an opportunity lost.
Other threads related to this build (which I'll collect together in a build thread if successful)