What tubes does the Ampeg V4Preamp use?

The Ampeg V4Preamp uses 5× 12AX7 preamp tubes.

When was the Ampeg V4Preamp produced?

The Ampeg V4Preamp was produced 1971–1980.

Ampeg V4Preamp preset

Verified · 80/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Ampeg V-4 preamplifier features a dual-channel design with 12AX7 tubes providing both normal and bright input options, a tube-driven tremolo oscillator, and a reverb driver circuit — all built into the preamp chassis of the 100-watt V-4 guitar head. The tone stack mirrors the Fender-derived mid-scooped topology but with Ampeg's own component values tuned for a slightly warmer, less scooped character. The V-4's preamp remains highly regarded for its musicality and the way it produces natural harmonic saturation when pushed.

Years produced: 1971–1980
Made in: USA
Channels: 2
Preamp tubes: 5× 12AX7

Tags: american.

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.