VHT Special 12/20 preset

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

The VHT Special 12/20 is a single-channel push-pull valve combo. A 12AX7 input stage feeds a Volume with pull-boost (footswitchable) and a single Tone control, then gain stages with a series effects loop (Send and Return levels) and a line out. A 12AX7 long-tail inverter drives two 6V6GTWs; a 6-position Depth rotary, a Texture switch, a MOSFET Watts control and an EL34/6V6 bias switch shape the power stage.

• Introduced: 2011
• Wattage: 20W
• Channels: 1
• Preamp tubes: 3× 12AX7
• Power tubes: 2× 6V6GTW

Tags: el84, clean, crunch, mid-wattage.

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.