What tubes does the Ampeg ST (Stonewall) - Channel 1 use?

The Ampeg ST (Stonewall) - Channel 1 uses 3× 12AX7 preamp tubes and 2× 6L6 power tubes.

When was the Ampeg ST (Stonewall) - Channel 1 produced?

The Ampeg ST (Stonewall) - Channel 1 was produced 1969–1973.

Ampeg ST (Stonewall) - Channel 1 preset

Close · 62/100 confidence. Most values readable. Minor gaps filled by inference from similar circuits.

The ST Stonewall is a bass amplifier from Ampeg's early 1970s lineup. Channel 1 delivers clean bass amplification with the warm 6L6 tone characteristic of Ampeg's bass amp designs. The Stonewall naming is unusual for Ampeg, possibly indicating a marketing sub-brand used for a specific market segment.

Years produced: 1969–1973
Made in: USA
Wattage: 30W
Channels: 2
Preamp tubes: 3× 12AX7
Power tubes: 2× 6L6

Tags: bass, american, vintage, low-wattage, clean.

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.