What tubes does the Ampeg B-15S - Channel One use?

The Ampeg B-15S - Channel One uses 2× 12AX7 preamp tubes and 2× 6L6 power tubes.

When was the Ampeg B-15S - Channel One produced?

The Ampeg B-15S - Channel One was produced 1971–1974.

Ampeg B-15S - Channel One preset

Verified · 83/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Ampeg B-15S was a higher-powered variant of the Portaflex concept introduced in the early 1970s, designed to deliver more stage volume while retaining the warm, full-bodied Portaflex character. As bass players began needing more headroom in live settings during the early 1970s, Ampeg responded with updated Portaflex designs that pushed more wattage while preserving the beloved tonal signature of the original B-15N.

Years produced: 1971–1974
Made in: USA
Wattage: 60W
Channels: 1
Preamp tubes: 2× 12AX7
Power tubes: 2× 6L6

Tags: american, vintage, 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.