Airline GDR-8516A - Channel A preset

Verified · 92/100 confidence. Complete schematic. All component values readable. Parameters derived directly from the circuit.

The Airline GDR-8516A is a two-channel Montgomery Ward tube amp with a remote preamp control panel. Channels A and B each have three instrument or mic inputs, one half of a 12AX7 and their own Bass, Treble and Volume. In the main chassis a second 12AX7 adds two gain stages ahead of a 6SN7GT long-tail inverter driving two 6L6s. A 6AU6 oscillator gives vibrato with Strength, Speed and a footswitch, and a 5Y3GT rectifies the supply.

Tags: american, vintage, 6l6, vibrato, two-channel, mid-wattage.

Schematic-derived preset files for the Neural DSP Quad Cortex and 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.