QSC RMX850A

Power Amplifier

QSC RMX850A is a 2RU rackmount power amplifier designed for live sound reinforcement, installed audio systems, and mobile PA applications. With two Class AB output channels, strong 2-ohm performance, and practical protection features, it gives DJs, bands, venues, and production crews a reliable way to drive passive loudspeakers.

QSC RMX850A Competitive Differences

• Delivers 300 watts per channel at 4 ohms and up to 430 watts per channel at 2 ohms in stereo mode
• Class AB amplifier design with high-current toroidal transformers for low-noise, dependable output
• Selectable 30 Hz and 50 Hz low-frequency filters help protect speakers and improve usable headroom
• Independent defeatable clip limiters reduce distortion during demanding live sound use
• Includes balanced XLR, 1/4-inch TRS, and Euro-style input connections for flexible system integration

QSC RMX850A Description

The QSC RMX850A is built for users who need a rugged, straightforward amplifier for passive PA speakers, monitors, or installed sound systems. Its 2-channel design can operate in stereo or bridge-mono mode, giving it the flexibility to handle a range of live sound and fixed installation setups.

With Class AB output circuitry and high-current toroidal transformers, the RMX850A is designed to deliver clean power with dependable performance, even when driving lower-impedance loads. At 4 ohms, it produces 300 watts per channel, while 2-ohm operation provides up to 430 watts per channel for demanding speaker configurations.

Front-panel gain controls make level adjustment simple, while signal, clip, protect, and power LEDs provide clear system status at a glance. User-defeatable clip limiters help control distortion, and selectable low-frequency filters at 30 Hz and 50 Hz help protect loudspeakers from excessive low-end movement.

The chassis is designed for rackmount use with forced-air cooling, and the rear panel includes both professional input and output connection options. XLR, 1/4-inch TRS, and Euro-style balanced inputs are provided, along with Neutrik Speakon and touch-proof binding post outputs for compatibility with a wide range of sound systems.

RMX850A Features

• 2-channel rackmount power amplifier
• 2RU chassis for standard equipment racks
• Class AB output circuit design
• Stereo and bridge-mono operating modes
• High-current toroidal transformers
• Independent user-defeatable clip limiters
• Selectable 30 Hz and 50 Hz low-frequency filters
• Front-panel gain controls for each channel
• Signal, clip, protect, and power LED indicators
• Balanced XLR, 1/4-inch TRS, and Euro-style input connections
• Neutrik Speakon and touch-proof binding post output connections
• Continuously variable speed fan cooling
• Full short circuit, open circuit, thermal, ultrasonic, and RF protection

RMX850A Specifications

• Channels: 2
• Amplifier Class: Class AB
• Rack Spaces: 2RU
• Stereo Power Output at 8 Ohms: 200W per channel, EIA 1 kHz at 0.1% THD
• Stereo Power Output at 8 Ohms: 185W per channel, FTC 20 Hz to 20 kHz at 0.1% THD
• Stereo Power Output at 4 Ohms: 300W per channel, EIA 1 kHz at 0.1% THD
• Stereo Power Output at 4 Ohms: 280W per channel, FTC 20 Hz to 20 kHz at 0.1% THD
• Stereo Power Output at 2 Ohms: 430W per channel, EIA 1 kHz at 0.1% THD
• Bridge-Mono Power Output at 8 Ohms: 600W, EIA 1 kHz at 0.1% THD
• Bridge-Mono Power Output at 8 Ohms: 530W, FTC 20 Hz to 20 kHz at 0.1% THD
• Bridge-Mono Power Output at 4 Ohms: 830W, EIA 1 kHz at 0.1% THD
• Signal-to-Noise Ratio: > -100 dB
• SMPTE-IM Distortion: < 0.01%
• THD at 20 Hz to 20 kHz, 10 dB Below Rated Power: < 0.03%
• THD at 1 kHz, Full Rated Power: < 0.03%
• Input Sensitivity: 1.15V, +3.4 dBu at 8 ohms
• Voltage Gain: 31.6x, 30 dB
• Damping Factor: > 300 at 8 ohms
• Input Impedance: 10 kOhms balanced, 20 kOhms unbalanced
• Frequency Response: 20 Hz to 20 kHz, +0/-1 dB
• Frequency Response -3 dB Points: 5 Hz to 50 kHz, LF filter bypassed at 8 ohms
• Input Connectors: 2 x 3-pin XLR, 2 x 1/4-inch TRS, active balanced 3-pin Euro-style detachable terminal block
• Output Connectors: 2 x Neutrik Speakon, touch-proof binding posts
• Cooling: Continuously variable speed fan, back-to-front airflow
• Front Panel Controls: Channel 1 gain knob, Channel 2 gain knob, C switch
• Rear Panel Controls: 10-position DIP switch
• Indicators: Power-on green LED, signal yellow LED per channel, clip red LED per channel, protect red LED per channel
• Power Consumption: 4.5A
• Power Consumption at 1/8 Power Pink Noise, 4 Ohms: 6.6A
• Power Requirements: 100V, 120V, or 230V AC, 50 to 60 Hz, factory configured
• Plug Type at 100/120V: NEMA 5-15
• Plug Type at 230V: CEE7/7
• Dimensions: 3.5 x 19.0 x 15.9 in (89 x 482 x 404 mm)
• Weight: 35.0 lb (15.9 kg)

QSC RMX850A (QSC RMX-850-A)