What tubes does the Ampeg B-42X Jupiter 42 - Channel 1 use?

The Ampeg B-42X Jupiter 42 - Channel 1 uses 3× 12AX7 preamp tubes and 4× 6L6 power tubes.

When was the Ampeg B-42X Jupiter 42 - Channel 1 produced?

The Ampeg B-42X Jupiter 42 - Channel 1 was produced 1967–1971.

Ampeg B-42X Jupiter 42 - Channel 1 preset

Verified · 82/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The B-42X Jupiter 42 is a larger model in Ampeg's Jupiter bass amplifier series, offering more power with four 6L6 output tubes. Channel 1 delivers clean, punchy bass tone with adequate headroom for small to medium venues. The Jupiter series provided affordable access to Ampeg quality at a lower price point.

Years produced: 1967–1971
Made in: USA
Wattage: 40W
Channels: 2
Preamp tubes: 3× 12AX7
Power tubes: 4× 6L6

Tags: bass, american, vintage, mid-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.