Supro S6424 - Channel 1 preset

Verified · 90/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Supro S6424 is a two-channel Valco combo from the early 1960s. Each channel has High and Low inputs into its own half of a 12AX7 and its own Volume and Tone controls. A 12AX7 tremolo oscillator with Speed, Intensity and a footswitch modulates the circuit. A second 12AX7 provides gain and a paraphase-style phase inverter for two 6973s, cathode-biased through a shared 250-ohm resistor, into a 12-inch 8-ohm speaker. A 5Y3 valve rectifier supplies about 350 V.

• Made in: USA
• Channels: 2
• Preamp tubes: 3× 12AX7
• Power tubes: 2× 6973

Tags: american, vintage, tremolo, two-channel.

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).

Gridleak extracts amp parameters from original circuit schematics using AI vision — component values, gain staging, tone stack topology, tube types — then generates native preset files for every supported modeler. Every extraction is scored 0–100 and the score is published.