Just picked up a two output Audio Guild converted to a head. As-received very interesting tone and cool vibrato. Love that clean creamy 7591 sound and, in this amp, all ceramic coupling caps lend a familiar period tone. In general, though, the unit seems quite well made. Only two problems with it: the reverb motorboats and the old US 7591s are kinda soft. I'm running low on old stock 7591s since I have several Ampegs. The sound deteriorates after it has been on for a while. Probably needs a recap and a fresh set of 7591s. Peering inside, it looks like the reverb send is tube but the recovery is 70s transistor. Does anybody have a schematic for this amp (or its mono sister)? I've been looking around for one for a while, since I have an extra bare chassis specimen of this amp, but never found anything. Still trying to figure out all of the switching. There are four inputs. low and high gain, on two channels plus a dual input jack with a switch to select between channels. I think the two outputs are high pass and low pass, each with its own set of 7591s and output trans. original cab had an 8" and a 12" in separate sealed compartments, if I'm not mistaken. And then there is a knob labeled "Ultraflex Balance" that appears to mix the bass and treble channels. Freaky setup indeed! Who else in TDPRI land is using one of these Audio Guild amps? Seems to have some serious potential!