What tubes does the Ampeg V4Pre Jp use?

The Ampeg V4Pre Jp uses 4× 12AX7 preamp tubes.

When was the Ampeg V4Pre Jp produced?

The Ampeg V4Pre Jp was produced 1971–1980.

Ampeg V4Pre Jp preset

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

The V4 preamp Japanese version schematic documents regional adaptations for the Japanese market. Power supply modifications and component substitutions for Japanese voltage standards may be reflected in this variant. An essential reference for restoring Japanese-market V4 amplifiers.

Years produced: 1971–1980
Made in: USA
Channels: 2
Preamp tubes: 4× 12AX7

Tags: american, vintage, 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.