Sound Electronics 505R - Channel 2 preset

Close · 74/100 confidence. Most values readable. Minor gaps filled by inference from similar circuits.

The Sound Electronics Model 505R is a two-channel valve combo with reverb and tremolo. Each channel has two inputs, its own 7025 with a Treble control and a Volume between its two stages, and the channels are combined through a rotary selector. Half a 12AU7A drives a transformer-coupled spring reverb, recovered by a 7025 with level controls; the other half is a split-load phase inverter for two 7868 output pentodes. A 7025 tremolo oscillator with footswitch modulates the output-stage bias.

• Channels: 2
• Preamp tubes: 4× 7025, 1× 12AU7A
• Power tubes: 2× 7868

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

Schematic-derived preset files for 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.