The heavy-duty RMX 4050a 2-Channel 850W Power Amplifier from QSC is built to handle 2-ohm loads. It features a three-tier, Class H design that is extremely efficient at real-world power levels while wasting less AC. Designed for versatility, the RMX 4050a includes balanced 1/4-inch (6.3 mm) TRS, XLR, and barrier strip inputs, as well as touch-proof binding post and Neutrik Speakon® outputs. Its selectable low-frequency filters (30 Hz or 50 Hz) protect speakers while increasing headroom, and independent DC and thermal overload protection function on each channel automatically protect the amp and any connected speakers. Among its other premium features are front-panel controls for easy access and gain adjustment, as well as easy-to-read, LED indicators for signal and clip monitoring.
More about QSC’s RMX Power Amplifier Series
The RMX series of power amplifiers from QSC is specifically built so you can achieve professional-caliber performance without breaking the bank. Members of the series are comprised of three 2-rack space models (with a power range of 430 to 1200 watts per channel at 2 ohms) and two 3-rack space models (with a power range of 2000 to 2500 watts per channel at 2 ohms). All models sport a compact chassis (less than 16” deep), resulting in a build that’s easy to incorporate into any size of setup.
Power amplifiers are beneficial wherever you have a low-level audio signal that needs a boost. This includes sound reinforcement, live concerts, entertainment, and special events, portable PA, home audio (theater, studio, office), or instrumental performances. In particular, a common need for power amplifiers is any audio setup that uses passive loudspeakers. Choose from a variety of power amplifier models to meet specific wattage or channel configuration requirements for your particular project.
Boasting a comprehensive set of features, including XLR and 1/4-in balanced inputs, Speakon® and binding post outposts for convenient connectivity, user-defeatable clip limiters, and selectable low-frequency filters to optimize sonic performance—RMX power amps are packed with the functionality you need to power your project.
QSC RMX 4050a Features
- Compact size - up to 2500 watts in two rack spaces, or 5000 watts in three rack spaces
- High-current toroidal transformers, for greater 2-ohm power and low noise
- Independent user-defeatable clip limiters reduce distortion
- Selectable low-frequency filters (30 Hz or 50 Hz) protect speakers and increase headroom
- The 4000-watt RMX4050a operates on a standard 15 amp plug (120V)
- Both the RMX4050a and the RMX5050a feature a dual mono, high-current power supply for increased reliability and performance
- The RMX4050a's particularly exceptional combination of cooling capacity and electrical efficiency provides robust thermal performance suitable for high continuous power in 2-ohm stereo or 4-ohm bridged applications.
- Balanced 1/4" (6.3 mm) TRS, XLR, and barrier strip inputs
- Touch-proof binding post and Neutrik Speakon® outputs
- Front mounted gain controls for easy access
- Signal and clip LED indicators for monitoring performance
- Independent DC and thermal overload protection on each channel automatically protects amplifier and speakers
- RMX 4050a 2-Channel 850W Power Amplifier1
- Three Year Warranty plus optional 3-year extended service contract1
- Output Power per Channel
- 8Ω, FTC 20 Hz–20 kHz, 0.1% tdD: 800 (650* *) W
- 8Ω, EIA 1 kHz, 0.1% tdD: 850W
- 4Ω, FTC 20 Hz–20 kHz, 0.1% tdD: 1300W
- 4Ω, EIA 1 kHz, 0.1% tdD: 1400W
- 2Ω, FTC 20 Hz–20 kHz, 1% tdD: 1600W
- 2Ω, EIA 1 kHz, 1% tdD: 2000W
- Power, Bridge-Mono Mode
- 8Ω, FTC 20 Hz–20 kHz, 0.1% tdD: 2600W
- 8Ω, EIA 1 kHz, 0.1% tdD: 2800W
- 4Ω, EIA 1 kHz, 1% tdD: 4000W
- Signal to Noise (20 Hz–20 kHz)-100 dB
- Distortion (SMPTE-IM)< 0.02%
- Input Sensitivity at 8Ω1.42V (+5.3 dBu)
- Voltage Gain64x (36 dB)
- Output Circuitry3-tier Class H
- Current Draw (120 V AC)
- Typical, 1/8 power pink noise at 4Ω*: 10.0A
- Severe, 1/3 power pink noise at 4Ω*: 20.1A
- AC Mains Plug
- 100/120V: NEMA 5-15
- 2:30W: CEE7/7
- Distortion (typical)
- 20 Hz–20 kHz, 10 dB below rated power: < 0.02% tdD, 4Ω and 8Ω
- 1 kHz and below, full rated power: < 0.02% tdD, 4Ω and 8Ω
- Frequency Response20 Hz–20 kHz: +0/-1 dB -3 dB points: 5 Hz and 50 kHz (LF filter bybassed, 8Ω)
- Damping Factor (1 kHz and below)> 250 at 8Ω
- Input Impedance10 kΩ unbalanced; 20 kΩ balanced
- Input Stage Clipping6.4 V rms (+18 dBu)
- CoolingContinuously variable speed fan, back-to-front air flow
- Connectors (each channel)
- Input: Active balanced; 3-pin Euro-style detachable terminal block and XLR (pin 2+)
- Output: Touch-proof binding posts; Neutrik Speakon®
- Controls
- Front: AC switch; Channel 1 & 2 gain knobs
- Rear: 10-position DIP switch
- LED IndicatorsPower on: Green; Signal: Yellow (1 per channel); Clip/Protect: Red (1 per channel)
- Amplifier ProtectionFull short circuit, open circuit, tdermal, ultrasonic, RF protection. Stable into reactive or mismatched loads
- Load ProtectionTurn-on/off muting; AC coupling (850, 1450); Triac crowbar (1850HD, 2450, 4050HD, 5050) on each channel
- Product Dimensions (H×W×D)5.25 (3 RU) × 19 × 15.9 in; 132 (3 RU) × 482 × 404 mm
- Carton Dimensions (H×W×D)24 × 22 × 9 in; 610 × 560 × 229 mm
- Net Weight68 lbs (30.8 kg)
- Shipping Weight77 lbs (34.9 kg)
- Power Requirements100, 120, 230V AC (factory configured), 50–60Hz
