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QSC RMX850a Power Amplifier (300 W per Channel)

QSC RMX850a Power Amplifier (300 W per Channel)


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Product Highlights

  • 300 Watts per Channel 4Ω
  • 830 Watt Bridgeable Mono Mode 4Ω
  • LED Indicators for Power, Signal, Clip
  • Built-In Protection Circuits
  • User-Defeatable Clip Limiters
  • Balanced 1/4" TRS, XLR, and Strip Inputs
  • Neutrik Speakon Output Connectors
  • High-Current Toroidal Transformers
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You Pay: $399.99

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The 300 watts per channel 4Ω QSC RMX850a Power Amplifier is a 2RU rack mountable amplifier designed for live sound reinforcement applications. The amplifier features two Class AB output channels that can operate in either stereo or mono bridge mode. The unit operates on a standard 15 amp plug and utilizes high-current toroidal transformers for less noise and better performance when pushing a 2 ohm load. To reduce distortion, the amplifier utilizes independent user-defeatable clip limiters and includes LED indicator lights to show the presence of the signal and when the signal is clipping.

The chassis of the amplifier is designed with front to rear cooling vents and includes selectable low-frequency filters at 30 Hz and 50 Hz to protect speakers from bottoming out and improve headroom when driving mid and high frequencies. The front panel of the unit features two gain control knobs for easy access and each channel is protected by a dedicated DC and thermal overload protection circuit. For inputs, the back of the unit accepts both balanced 1/4" and XLR inputs. For outputs, the unit features both Neutrik Speakon and touch-proof binding post connections.

Power Rating Stereo mode (both channels driven)
8 Ω FTC 20 to 20,000 Hz at 0.1% THD: 185 W
8 Ω EIA 1,000 Hz at 0.1% THD: 200 W
4 Ω FTC 20 to 20,000 Hz at 0.1% THD: 280 W
4 Ω EIA 1,000 Hz at 0.1% THD: 300 W
2 Ω EIA 1,000 Hz at 0.1% THD: 430 W

Bridge-mono mode 8 Ω FTC 20 to 20,000 Hz at 0.1% THD: 530 W
Bridge-mono mode 8 Ω EIA 1,000 Hz at 0.1% THD: 600 W
Bridge-mono mode 4 Ω EIA 1,000 Hz at 0.1% THD: 830 W
Signal-to-Noise Ratio > -100 dB
Distortion SMPTE-IM: < 0.01%

For 8 and 4 Ω load
THD for 20 to 20,000 Hz at 10 dB below rated power: less than 0.03%
THD for 1,000 Hz at full rated power: less than 0.03%
Input Sensitivity 1.15 V (+3.4 dBU) at 8 Ω
Voltage Gain 31.6x (30 dB)
Circuit Type Class AB
Power Consumption 4.5 A

1/8 power pink noise at 4Ω 6.6 A
Damping Factor > 300 at 8Ω
Input Impedance 10 kΩ balanced
20 kΩ unbalanced
Frequency Response 20 to 20,000 Hz +0/-1 dB -3 dB points
5 Hz to 50,000 Hz (LF filter bypassed/8 Ω)
Input Connections Active balanced 3-pin Euro-style detachable terminal block
2 x 3-pin XLR
2 x 1/4" TRS
Cooling Continuously variable speed fan, back-to-front airflow
Output Connectors Touch-proof binding posts
2 x Neutrik Speakon
Controls Front Panel AC switch
Channel 1 gain knob
Channel 2 gain knob
Controls Rear Panel 10-position DIP switch
Indicators Power-on: green LED
Signal: yellow LED (1 per channel)
Clip: red LED (1 per channel)
Protect: red LED (1 per channel)
Power Requirements 100, 120, 230 VAC at 50 to 60 Hz (factory configured)
Protection Amplifier: Full short circuit, open circuit, thermal, ultrasonic, RF protection. Stable into reactive or mismatched loads

Load: Turn-on/off muting/AC coupling (850, 1450)/ Triac Crowbar (1050HD, 2450, 4050HD, 5050) on each channel
Rack Spaces 2
Plug Type 100/120V: NEMA 5-15

230V: CEE7/7
Dimensions (H x W x D) 3.5 x 19.0 x 15.9" (89.0 x 482 x 404 mm)
Weight 35.0 lb (15.9 kg)
QSC RMX850a Power Amplifier (300 W per Channel)
  • Power Cord
  • Limited 3-Year Warranty Extendable by Additional 3-Year Service Contract
  • Be the first to review this item


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