What tubes does the Ampeg SBT Preamp - Channel 2 use?

The Ampeg SBT Preamp - Channel 2 uses 2× 12AX7 preamp tubes.

When was the Ampeg SBT Preamp - Channel 2 produced?

The Ampeg SBT Preamp - Channel 2 was produced 1969–1973.

Ampeg SBT Preamp - Channel 2 preset

Close · 78/100 confidence. Most values readable. Minor gaps filled by inference from similar circuits.

The SBT Preamp Channel 1 documents the input stage of the Ampeg SBT bass amplifier from the early 1970s. The SBT was a solid-state bass amplifier; this preamp schematic covers the tube-input stage that preceded the transistor power section. An interesting hybrid design from Ampeg's transitional period between all-tube and solid-state bass amps.

Years produced: 1969–1973
Made in: USA
Channels: 1
Preamp tubes: 2× 12AX7

Tags: bass, american, vintage, preamp.

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.