Lectrolab R400 preset

verified · 93/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Lectrolab R400 is a late-1950s American tube combo from the catalog-sold Lectrolab line. Inputs 1 and 2 share one 6SN7GT triode while Input 3 has its own, both feeding a single Volume control, then two more 6SN7GT stages lead to a single-ended, cathode-biased 6V6GT with one Tone control. A 5Y3GT rectifier supplies about 300 volts. The later R400C swapped to an EL84 and two 12AX7s and added tremolo.

• Made in: USA
• Channels: 1
• Preamp tubes: 2× 6SN7GT
• Power tubes: 1× 6V6GT

Tags: american, vintage, clean.

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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