← Topology
Tone stack

per-channel-tb

3 amps in the archive

Every per-channel-tb amp

The matching circuits, with the neighbouring topology choices shown for contrast.

CircuitEraOutputTubes Phase inverterOutput-stage biasRectifier
6G6-B 1963–1964 50 W 7025, 7025, 7025, 7025, 5881, 5881 long-tailed-pairfixedsolid-state
B15N 1961–1964 25 W 6SL7, 6SL7, 6SL7, 6L6GC, 6L6GC, 5AR4 paraphasefixed5AR4
S1484 1963–1967 60 W 12AX7, 12AX7, 6CG7, 12AX7, 6CG7, 12AX7, 6L6GC, 6L6GC cathodynefixed1N3194 ×4 (capacitor multiplier) + 1N3754 (bias)

Circuits