Power Amplifier Modules with Passive Cooling

(GRX-FR, GRX-BiFR and GRX-SUB Series)

This line of plate-mounted power amplifier modules is solidly built for installation on rear panels of active loudspeaker systems, both full range loudspeakers and subwoofers. Every module has a large convection cooled heatsink on the outside, a toroidal transformer, and a 1.6mm thick metal plate chassis. All models share the same input/link balanced XLR connectors, volume control knob, status LEDs (SIGNAL, LIMIT, PROTECT and POWER), and ground lift switch. Subwoofer modules have left/right balanced input XLRs and corresponding linked outputs, as well as high-pass balanced output XLRs to connect active satellite speakers. Subwoofer modules have a built-in full-featured stereo X-over with a three position frequency switch and a phase switch; the X-over can be set up as B3 or LR4. All models also have a built-in high quality clip limiter to assist the loudspeaker in providing the highest possible SPL without damaging the amplifier and the speaker components, and to fight user abuse to the loudspeaker. All modules are built with the same time-proven topology of efficient linear 2-tier class H circuitry for high performance, enhanced reliability, and high power-to-weight factor. The amplifiers employ very solid construction to fight speaker-born vibrations. Enhanced thermal design and meticulously developed PCB layout provide premium performance and long-term reliability. All modules enjoy many levels of protection starting with multi-pole SOA-based protection of high current output stage, to triac-based speaker protection, to thermal protection of the output stage and the power transformer, and many others. We employ no output relays, as their contacts would deteriorate due to speaker-born vibrations. Also, to protect the audience and the loudspeakers, a soft sound ramp is employed to control the output level after the amplifier is switched on. Amplifiers can be fully customized to match particular loudspeakers' power, filtering and EQs.

Product specs coming soon.