What tubes does the Fender Twin Reverb AB568 - Normal use?

The Fender Twin Reverb AB568 - Normal uses 3× 7025, 1× 12AX7, 2× 12AT7 preamp tubes and 4× 6L6GC power tubes.

When was the Fender Twin Reverb AB568 - Normal produced?

The Fender Twin Reverb AB568 - Normal was produced 1968.

Fender Twin Reverb AB568 - Normal preset

Verified · 91/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Twin Reverb AB568 is the first CBS-era revision of the Twin Reverb circuit, from 1968. Normal and Vibrato channels each have volume, treble, middle and bass with a bright switch. The Vibrato channel adds 12AT7-driven spring reverb with a 7025 recovery stage and 12AX7 optical vibrato with speed and intensity. A 12AT7 long-tail inverter in the revised AB568 arrangement drives four 6L6GCs on a silicon rectifier.

Years produced: 1968
Made in: USA
Wattage: 85W
Channels: 2
Preamp tubes: 3× 7025, 1× 12AX7, 2× 12AT7
Power tubes: 4× 6L6GC

Tags: american, vintage, silverface, clean, reverb, vibrato, 6l6.

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.