Circuit is a C3g Pentode voltage amplifier with VR tube screen regulator, then 300b driver to 1:1 amorphous interstage to GM70 grid. Output TX 7k amorphous. Driver and 300b supply, series regulator using 6080, ecl82 and 0d3 (Steve bench inspired). TJ-Meshplate 300b, running 330v @ 55ma. Copper plate GM70 running 1020v @ 110ma.
All transformers by Automatic Electric Europe
GM70 and 300b DC heated using TentLabs units.
Rough specs, -3dB points (5w into 8ohm) 18Hz, 52kHz. 3% distortion reached at 42w into 8 ohm.