Carlsbro 100/7 PA & Slave preset

Verified · 88/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Carlsbro 100/7 PA is a 100-watt valve PA head. Inputs 1 to 6 run in pairs through three ECC83s and input 7 through a fourth, each input with its own volume, treble and bass, mixed into master treble, bass and volume with echo send and return sockets. A further ECC83 and an ECC81 long-tail inverter drive four fixed-bias EL34s with 100 V line and speaker taps. The slave version omits the input stages to serve as a power amp.

• Made in: UK
• Wattage: 100W
• Channels: 1
• Preamp tubes: 5× ECC83, 1× ECC81
• Power tubes: 4× EL34

Tags: british, vintage, el34, high-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.