Selmer Constellation 20 preset

verified · 82/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Constellation 20 is a valve combo from Selmer London’s 1960s line. Inputs 1 and 2 feed one ECC82 triode with its own volume, inputs 3 and 4 the other triode with a second volume, and both mix into an ECC83 stage with bass and treble controls. An ECC83 adds gain and phase splitting for a push-pull pair of EL84s, and the other ECC83 triode is a tremolo oscillator with speed, depth and an on/off switch. An EZ81 rectifies.

• Made in: UK
• Wattage: 20W
• Channels: 1
• Preamp tubes: 1× ECC82, 2× ECC83
• Power tubes: 2× EL84

Tags: british, vintage.

Schematic-derived preset files for the Neural DSP Quad Cortex and 16 Fractal and Line 6 modelers: Axe-Fx II/XL/XL+, Axe-Fx III, FM3, FM9, and the full Helix family (Floor, LT, Rack, HX Stomp, HX Stomp XL, Native).

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