I have been pondering for years about building some kind of Plexi / 2204 2-in-1. But the cost of the iron and the fact I have a lot of amps already always made me put it on the backburner. The other day I accidentally discovered these attached schematics and layouts on my PC. Have no idea where I found it, but Steve Luckey is the creator. But it's precisely what I want : a plexi and a 2203 preamp, in theory able to line out into any other power amp, or be converted into a full amp down the road if I so choose. I personally prefer just the preamp concept : it makes it useable with 5, 50, and 100w power amps. I could call it a ....Dual Super Lead ? How about a Super Lead Overdrive ? Or add a rectifier tube and call it ... Dual Rectifier? What I don't understand, and what I could use some help in, is figuring out what kind of power supply this pre-amp would need to get it to correct voltages. I assume a 1 watt power transformer would be sufficient and economical. But it would obviously need some sort of (diode) rectification to create the B+ necessary??? Here's a layout with a power amp and using a switch instead of two separate inputs. That gives me some ideas but I don't really want to bother with a full amp. I just want to build a preamp with the right voltage and a proper fuse. But I'd appreciate any insight about the power supply, or output concerns (correct impedance for an effects return?).