Final circuit layout, pot half-open ("gain half way") sound examples.
Parker Fly Classic bridge pickup into Fender GT40 modeling amp, out from headphones jack to M-Audio M-Track 2 interface.
Bandmaster patch followed by Bassman patch followed by no patch (as in a full range speaker) followed by clean guitar.
I used chords to better identify the frequency spread in the Pro Channel equalizer display of Cakewalk, followed by a muted chugging power chord and ending with a Townsend-style ringing final chord to compare the duration that each setting gives to the sustain.

Circuit One half-open sound examples

eddie chillington