Ampeg BT-15 / BT-15C / BT-15D / BT-18C - Channel 1 preset

Verified · 87/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The BT-15 family (BT-15, BT-15C, BT-15D and BT-18C) are Ampeg's late-1960s solid-state bass amps. Each of the two channels has a 2N4360 FET input, volume, bass and treble controls and an Ultra High switch. The driver stage feeds a quasi-complementary output of four RCA power transistors rated 100 watts into 4 ohms (65 W into 8), and the front panel is lit by an electroluminescent strip.

Tags: american, bass, solid-state, two-channel, high-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.