RMX Series power amplifier — 200W x 2 at 8 ohms, 830W x 1 at 4 ohm bridged
Our take on the QSC RMX850a by Crutchfield's Bob Bihlmayer
Loud and clear
When it's time to let the music do the talking, you want a loud, clear voice driving your speakers. QSCs RMXa power amplifiers give you the power you need to fill your venue with clear, accurate sound. Whether you're working in a hall, a club, or a house of worship, the RMXa Series amps will make your performance speak for itself.
Strong and safe
The RMX850a 2-channel amplifier delivers 200 watts EIA per channel at 8 ohms, 300 watts at 4 ohms, and up to 830 watts bridged at 4 ohms. Its independent thermal and short/open circuit protection for each channel automatically protects the amplifier and speakers, while the independently defeatable clipping limiters give your speakers even more protection. You can also switch on high-pass filters at 30 Hz or 50 Hz to further protect your speakers from overloading.
The front-mounted gain controls offer easy access, and the signal and clip LEDs give you immediate feedback on the amp's operation. In back, you'll find screw terminal, 1/4", and XLR inputs, with Neutrik Speakon® and binding post outputs. And the RMX850a is rackmountable, so you can gang it with additional amps or signal processing gear.
- 2-channel Pro Audio amplifier
- power output at 20-20,000 Hz
- 185 watts FTC per channel at 8 ohms
- 280 watts FTC per channel at 4 ohms
- power output at 1 kHz:
- 200 watts EIA per channel at 8 ohms
- 300 watts EIA per channel at 4 ohms
- 600 watts EIA (mono) at 8 ohms in bridged mode
- 830 watts EIA (mono) at 4 ohms in bridged mode
- frequency response: 20-20,000 Hz
- signal-to-noise ratio: -100 dB
- inputs: XLR, 1/4" TRS, and screw terminals for channels A and B
- outputs: Neutrik Speakon jacks, 5-way binding posts
- independent right- and left-channel gain controls on front panel
- variable speed fan for heat dissipation
- DC, short circuit, and overload protection
- front-panel LEDs indicate Power and Clipping
- dimensions: 3-1/2"H x 19"W x 16"D
- weight: 35 lbs.
- warranty: 3 years
- Our 60-day money-back guarantee
What's in the Box:
- 2-Channel amplifier
- 58" AC power cord
- 2 Rack-Mount brackets (installed)
- Hookup Drawings
- Important Safety Instructions
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Features and Specs
|Number of Channels||2|
|Watts per channel 8 ohms||185|
|Watts per channel 4 ohms||280|
|Watts per channel 2 ohms||430|
2-Channel Amplifier: The QSC RMX 850a employs a two-channel class AB amplifier with a high-current toroidal transformer for low impedance, greater power, and little noise. RMXa power ratings:
|Operation Modes||Ohm Load||Power Rating||Frequency Response||THD|
Operation Modes: The amplifier can be set for normal Stereo operation, Parallel input Mode, or Bridge Mono Mode.
- Stereo Mode: Each channel remains independent; the amplifier may be used for two different signals.
- Parallel Mode: This setting connects both inputs together; one signal feeds both channels. Each channel's Gain control and loudspeaker connection remain independent.
- Bridge Mode: This setting combines both channels into a single channel with twice the output power. Use only the first channel's input and Gain control. Set the second channel's Gain control at minimum.
Inputs: The QSC RMXa series amplifier provides XLR, 1/4" TRS, and barrier strip screw terminal input connectors to connect your external audio sources.
Outputs: The RMXa series amplifier offers Speakon (NL4) and binding post output connectors to connect your loudspeakers.
Independent Controls: The QSC RMXa series amplifier offers independent Gain, Clip Limiter, and Lower Frequency Filters for each channel (1-2). These controls are front-mounted for easy access.
- Gain: Turn the Gain controls for each channel (1-2) clockwise to increase Gain and counterclockwise to decrease Gain. At the maximum setting, the voltage Gain of the amplifier is +36 dB.
- Clip Limiters: Each channel has a Clip Limiter with its own on-off switch to reduce distortion. The limiter only responds to actual clipping, and automatically compensates for load and voltage variations. Clip limiting is generally recommended, especially to protect high frequency drivers.
- Low Frequency Filters: Each channel has a 12dB per octave Low Frequency Filter (30 or 50Hz) to prevent cone over-excursion, making more power available for the loudspeaker's rated frequency range. This reduces distortion and prevents amplifier overload. The Filter should only be turned off for driving subwoofers with special low frequency capability. Otherwise, unless you have filtering in the signal path preceding the amplifier, use the Low Frequency Filter
LED Indicators: The LED indicators on the front-panel of the amplifier can be used to monitor system operation and identify common problems.
- Power: A single blue indicator will illuminate when powered on; no illumination when powered off.
- Signal: A green indicator for each channel will illuminate when the input signal exceeds -35 dB. As signal approaches full power, the indicator will illuminate continuously.
- Clip: A red indicator for each channel will illuminate whenever the amplifier is driven beyond full power.
- Protect: A single red indicator will illuminate when the amplifier goes into protect mode. Under normal operation, this indicator will not be illuminated.
Protection Circuitry: Independent DC and thermal overload protection on each channel automatically protects the amplifier and your connected speakers.
Cooling Fan: Cool air is drawn into the rear of the amplifier by the cooling fan. Warm air exits the front of the amplifier.
Our Product Research Team
At Crutchfield, you'll get detailed, accurate information that's hard to find elsewhere. That's because we have our own in-house Product Research team. They verify what’s in the box, check the owner's manual, and record dimensions, features and specs. We stay on top of new products and technologies to help people make informed choices.
Why did you buy this?
Very good Amplifier for the price... have used this brand for years. [ JOHN May 18, 2018 ]
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