Serpens

The Ground Control Audio Serpens is a feed-forward optical compressor using an LED-LDR (light-dependent resistor) circuit to control signal dynamics. Its side-chain employs a half-wave rectifier and an adjustable RC discharge circuit to regulate compression decay time. A dedicated sensitivity control adjusts how strongly the side-chain responds to the input signal, while the main gain control works alongside it to shape compression behavior, functioning similarly to threshold and ratio adjustments. An integrated blend control allows the compressed signal to be mixed with the unaffected dry signal for parallel compression. Introduced in 2017, the Serpens is designed to preserve the input signal's tonal characteristics while providing adjustable dynamic control. It features mechanical true bypass and requires a 9V DC center-negative power supply, drawing approximately 12 mA.