QSC GX3 425W 2-Channel Power Amplifier

The QSC GX3 425W 2-channel power amplifier delivers reliable portable sound reinforcement for entertainers, DJs, musicians, and AV teams. It provides 300W per channel at 8 ohms and 425W per channel at 4 ohms, with flexible inputs, professional speaker outputs, and built-in amplifier protection.

Designed for portable PA systems, compact equipment racks, and live performance rigs, this QSC GX3 power amplifier gives users a dependable 2-channel amp for passive speakers. It is a strong choice for buyers needing a lightweight rackmount power amplifier, a portable PA amplifier, or a compact amp with real-world headroom.

The GX3 features XLR, 1/4-inch TRS, and phono inputs for broad source compatibility, plus Speakon combo outputs and binding posts for common speaker wiring setups. GuardRail protection helps protect the amplifier and loudspeakers from temperature rise and overdrive, while the built-in crossover supports subwoofer/satellite system configurations.

Key Features

• Portable 2-Channel Power: Delivers 300W per channel at 8 ohms and 425W per channel at 4 ohms with both channels driven.
• Real-World Headroom: Optimized for 4-ohm and 8-ohm speaker systems commonly used by entertainers and mobile audio professionals.
• Flexible Inputs: XLR, 1/4-inch TRS, and phono input connectors support compatibility with a wide range of audio sources.
• Versatile Speaker Outputs: Speakon combo outputs accept 1/4-inch TS plugs or Speakon 2-pole and 4-pole plugs, while binding posts support other wiring systems.
• GuardRail Protection: Automatically protects the amplifier and loudspeakers from damage caused by temperature rise or overdrive.
• Built-In Crossover: Rear-panel crossover switch supports subwoofer/satellite operation with 100 Hz filtering.
• Compact Rack Depth: 10.1-inch chassis depth fits compact effects racks and portable rack systems.
• Front Panel Monitoring: Power, signal, and clip LEDs provide quick visual status during setup and performance.

Technical Specifications

• Brand: QSC
• Model: GX3
• Product Type: 2-channel power amplifier
• Status: Discontinued
• Output Power, 8 Ohms Continuous: 300W per channel, both channels driven
• Output Power, 4 Ohms Continuous: 425W per channel, both channels driven
• Distortion: Less than 0.02% at 8 ohms; less than 0.05% at 4 ohms, 1 dB below rated power at 1 kHz
• Signal To Noise: 100 dB, 20 Hz–20 kHz
• Input Sensitivity: 1.2V RMS
• Voltage Gain: 32.2 dB
• Output Circuitry: Class B
• Power Requirements: 6.3A at 1/8 power, pink noise at 4 ohms, 120V
• Frequency Response: 20 Hz–20 kHz, +0, -1 dB
• Dynamic Headroom: 2 dB at 4 ohms
• Input Impedance: Greater than 20 kOhms balanced
• Maximum Input Level: +24 dBu, 16V RMS
• Input Connectors: 3-pin XLR and 1/4-inch TRS balanced parallel connectors; phono unbalanced connector
• Output Connectors: Speakon, 1/4-inch, and binding posts
• Amplifier Protection: Short circuit, open circuit, thermal, and RF protection
• Load Protection: Protected against DC faults
• Front Panel Controls: Gain controls with 21 detents
• Front Panel Indicators: Red clip LEDs, green signal LEDs, and blue power LED
• Clip LED Threshold: 0.1% THD
• Signal LED Threshold: 35 dB below clipping
• Rear Panel Control: Full Range / Crossover switch
• Crossover: 100 Hz, 3rd order low-pass for subwoofer and 2nd order high-pass for top speaker
• Product Dimensions: 10.1" D x 19" W x 3.5" H
• Carton Dimensions: 24" x 15" x 6"
• Net Weight: 27 lbs
• Shipping Weight: 29.1 lbs
• Agency Approvals: UL, CE, RoHS/WEEE compliant
• Idle Current Draw And Heat: 0.2A, 44 BTU/hour at 120VAC
• 8 + 8 Ohms, 1/8 Power: 4.1A, 904 BTU/hour at 120VAC
• 8 + 8 Ohms, 1/3 Power: 6.1A, 1160 BTU/hour at 120VAC
• 8 + 8 Ohms, Full Power: 9.75A, 1109 BTU/hour at 120VAC
• 4 + 4 Ohms, 1/8 Power: 6.3A, 1515 BTU/hour at 120VAC
• 4 + 4 Ohms, 1/3 Power: 9.4A, 2105 BTU/hour at 120VAC
• 4 + 4 Ohms, Full Power: 15.0A, 2297 BTU/hour at 120VAC