Altec Lansing 1570A preset

Verified · 91/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Altec Lansing 1570A is a professional tube power amplifier for theater and sound reinforcement, with two 811-A transmitting triodes in class-B push-pull. A line input with level control and optional matching transformer feeds a 12AX7, a 6SN7GTB phase splitter and two 6W6GT drivers coupled to the 811-A grids through an interstage choke. Four 5U4GB rectifiers supply the high voltage, and the multi-tap output reaches a 70-volt line.

• Made in: USA
• Wattage: 175W
• Channels: 1
• Preamp tubes: 1× 12AX7, 1× 6SN7GTB, 2× 6W6GT
• Power tubes: 2× 811-A

Tags: american, vintage, power-amp, 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).

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