Description
The ST-GCA3 is a compact line level gain control amplifier that provides continuous automatic gain control to stabilize audio output levels. It raises low-level signals and reduces excessive peaks to maintain a consistent output. This unit is optimized for audio systems where stable levels and intelligibility are required.
The ST-GCA3 features switch-selectable AGC rates – SLOW for inaudible leveling of music and FAST for rapid correction of bursts and inconsistent sources. It provides wide dynamic range AGC and tight dynamic control to preserve program content while preventing clipping. Low-noise and low-distortion circuitry ensure high-fidelity gain management.
Performance specifications include an input nominal level of +4 dBu and a rated input range from -45 dBu to +20 dBu. The device delivers greater than 40 dB of AGC range while maintaining output within 3 dB, frequency response of 10 Hz to 20 kHz, and THD+N typically 0.05% at 1 kHz. Muting thresholds and response times are configurable for reliable operation in varied environments.
Connectivity is provided via balanced inputs and two balanced line outputs, with additional capacity for balanced mic-level signals into 150 ohms. Power is supplied at 24 Vdc using RDL SupplyFlex compatible wiring for ground-referenced or floating supplies. LED indicators show expansion and gain reduction to simplify visual monitoring during operation.
Typical applications include paging systems, intercoms, mic mixing, and background music systems where consistent levels are essential for intelligibility and listening comfort. The FAST AGC setting is particularly useful where sudden level bursts must be rapidly controlled. The SLOW AGC setting is designed to level music sources without introducing audible pumping.
Installation is straightforward due to the unit’s compact dimensions and low current draw of 40 mA at 24 Vdc. The chassis and controls are designed for professional AV integration and reliable long-term operation in ambient temperatures from 0° C to 55° C. The ST-GCA3 provides practical level control that improves system performance and listener experience.