Lehle Dual SGoS Hum-free ABY Switcher with MIDI

The Lehle Dual SGoS is a programmable ABY switcher that routes guitar signal to two amplifiers independently or in parallel, with MIDI control and transformer–isolated outputs to eliminate hum loops. Lehle's Transformer HZ high-end transformer provides galvanic isolation on outputs A and B, preventing ground loop noise when running dual amps. Gold-plated relay switching handles all routing, while onboard ground switches and phase inverters maintain signal integrity across the full frequency spectrum.

The unit features individual volume potentiometers that enter the signal path only when outputs A and B run simultaneously, allowing precise level matching between two amplifiers. Output T provides a buffered feed primarily intended for tuners, but also functions as a third amplifier output or secondary channel for amp B. Both main outputs include mute functions for silent tuning, while the gold-plated relays employ active pop-and-click suppression to eliminate switching transients. MIDI programme change commands enable remote preset recall when integrated with other Lehle SGoS switchers, particularly the D.Loop SGoS for expanded routing.

Features

• Transformer–isolated outputs A and B eliminate ground loop hum completely
• MIDI programme change control for remote switching and preset recall
• Gold-plated relay switching with active pop-and-click transient suppression
• Independent volume controls for outputs A and B when active simultaneously
• Output T provides buffered feed for tuner or third amplifier output
• Ground switches and phase inverters on both main outputs
• Mute function on outputs A and B for silent tuning
• Lehle Transformer HZ high-end transformer for galvanic output isolation