QSC GX3 Professional Power Amplifier 2x425W @ 4ohms 2U

GX3 Professional 2x425W Power Amplifier

GX Series amplifiers are ideal for professional entertainers who require maximum performance and portability on a limited budget. The hallmarks of the QSC brand - professional audio quality, meticulous engineering, precision manufacturing and long-term reliability - are all intrinsic to GX. Add contemporary styling, multiple input/output options, light weight, and advanced protection circuitry, and the GX Series clearly represents real value - something everyone can use.

The Right Amount of Power

GX amplifiers deliver just the right amount of power to the most popular speakers used by entertainers. Typically, loudspeaker manufacturers recommend an amplifier with power output equal to the speaker's Program (Music) Power rating or two times (2 x) the Continuous (RMS) Power rating.

The GX3 is ideal for speakers in the 300 W range, while the GX5 provides full performance for 500 W speakers and the GX7 outputs 725 W into an 8 ohm load. Owners of popular 4 ohm loudspeakers (such as dual-woofer, two-way models) will find the 700 W (4 ohm) power of the GX5 an ideal match while the GX7's 1000 W will very capably power many of today's popular subwoofers or two typical 8 ohm speakers per channel.

The GX3 uses the latest evolution of the QSC Grounded Collector output system, for optimum cooling of the critical power transistors. A true Class B biasing system combines maximum thermal efficiency with excellent audio performance. 

The GX5 uses a Class H system, based on key elements of the PL Series, (PLX, PL3, CX, DCA) almost doubling power in the same size and weight. QSC design expertise allows the output devices to shift from low-power to high-power rails in less than a millionth of a second, ensuring that the output power is always right where it needs to be without excess loss.

Optimum Cooling, Torodial Power Transformers, High Power-to-Weight Ratios

Both amplifiers use premium toroidal power transformers for reliable "mid-weight" performance. A variable-speed fan moves air crosswise through the amplifier, drawing cool air in over the power transformer, through the fan, and then over the heat sink. This keeps the transformer cool and allows a full size heat sink to fit in a down-sized chassis.

The GX7 adds the road-proven PowerLight supply to the Class H output section, for more overall output power and additional weight savings. The result is one of the highest power-to-weight ratios in the industry. A low-noise variable-speed fan with rear-to-front airflow keeps amplifiers and racks cool.

Stable Performance, Long Lasting Life

As always, GX Series amplifiers are fully protected from the usual hazards of the trade, ensuring stable performance and long life.

Full peak power whilst preventing detrimentral Overloads

GuardRail protection delivers full peak power while preventing detrimental overloads. During excessive clipping, or extreme overheating, GuardRail reduces gain just enough to preserve the integrity of the music, protect the speakers and keep the audience excited, without unprofessional distortion levels or shutdowns.

Subwoofers/Satellite Crossover

GuardRail protection delivers full peak power while preventing detrimental overloads. During excessive clipping, or extreme overheating, GuardRail reduces gain just enough to preserve the integrity of the music, protect the speakers and keep the audience excited, without unprofessional distortion levels or shutdowns.

Product Specifications

General

• 8 ohms / 1 kHz (both channels driven):  300 W
• 8 ohms / 1 kHz (single channel driven):  350 W
• 4 ohms / 1 kHz (both channels driven):  425 W
• 4 ohms / 1 kHz (single channel driven):  500 W
• Distortion (1 dB below rated power, 1 kHz):  8 ohms: less than 0.02%  |  4 ohms: less than 0.05%
• Signal to Noise (20 Hz - 20 kHz):  100 dB
• Input Sensitivity:  1.2 V rms
• Voltage Gain:  32.2 dB
• Output Circuitry:  Class B
• Power Requirements (1/8 power, pink noise at 4 ohms, 120V):  6.3 A
• Frequency Response:  20 Hz–20 kHz, +0, -1 dB
• Dynamic Headroom (4 ohms):  2 dB
• Input Impedance:  Greater than 20 kΩ (balanced)
• Maximum Input Level:  +24 dBu (16 V rms)
• Input Connectors (each channel):  3-pin XLR and 1/4" TRS, balanced, parallel  |  Phono, unbalanced
• Output Connectors (each channel):  Speakon®, 1/4", Binding posts
• Amplifier and Load Protection:  Short circuit, open circuit, thermal, RF protection  |  Load protected against DC faults
• Front Panel Controls and Indicators:  Gain controls, 21 detents  |  Red CLIP LEDs, proportional, 0.1% THD threshold  |  Green SIGNAL LEDs, threshold 35 dB below clipping  |  Blue POWER LED, AC on
• Rear Panel Controls:  Full Range / Crossover switch  |  100 Hz, 3rd order LP (sub), 2nd order HP (top)

Physical & Dimensions 

• Height:  89 mm 2RU
• Width:  483 mm
• Depth:  257 mm
• Net Weight:  12.1 kg
• Shipping Weight:  14.1 kg