background image

Features

• Power levels matched to the most popular 

speakers used by entertainers

• Optimized for maximum real-world 

headroom into 4

Ω

 and 8

Ω

 speaker systems

• Inputs: XLR, 1/4" TRS and phono input 

connectors for compatibility with any source

• Outputs: Speakon

® 

combo accepts, 1/4" 

(TS) plugs or Speakon 2-pole and 4-pole 

plugs (connects 2 poles only). Binding posts 

support all other speaker wiring systems

• Minimum depth chassis (10.1"/257 mm)  

fits in compact, inexpensive effects racks

• Lightweight – GX3 and GX5 less than 26 lbs 

(12.5 kg). GX7 only 15.5 lbs (7 kg)

*

• Detented gain controls for precise setting  

and matching of sensitivity

• GuardRail™ automatically protects the 

amplifier and loudspeakers from damage 

due to temperature rise or overdrive without 

shutting down the show 

• Front panel LEDs monitor Power, Signal  

and Clipping

• Subwoofer/Satellite crossover built-in

230V 16.5 lbs (7.5 kg)

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.
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 watt (Program) range, while the GX5 provides full 

performance for 500 watt (Program) speakers. The GX7 outputs 725 watts into an 8 ohm load. 

Owners of popular 4 ohm loudspeakers (such as dual-woofer, two-way models) will find the 700 

watt (4 ohm) power of the GX5 an ideal match while the GX7 1000 watts will very capably power 

many of today’s popular subwoofers or two typical 8 ohm speakers per channel.

Technical Notes

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.
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.
As always, GX Series amplifiers are fully protected from the usual hazards of the trade, ensuring 

stable performance and long life. 

GuardRail™

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. 

Subwoofer/Satellite Crossover 

A subwoofer reduces strain on the full-range speaker, allowing it to play louder, or letting a smaller 

speaker do the same job. The GX Series supports this mode with a Crossover switch that splits the 

full-range input entering Ch 1, sending 20 Hz -100 Hz to the sub (Ch 1) and 100 Hz - 20 kHz to the 

top box (Ch 2). The front panel gain controls balance the sub and top box, while GuardRail optimizes 

peak power into the sub and top individually, for greater musical impact and dynamic range. GuardRail 

optimizes peak power into the sub and top individually, for greater musical impact and dynamic range.

Choose the right GX amp for your speakers

Model  

GX3 

For 8

Ω

 speakers: 250 W – 350 W (program)

a

GX5 

For 8

Ω

 speakers: 400 W – 600 W (program)

b

GX7 

For 8

Ω

 speakers: 650 W – 800 W (program)

c

  

GX Series

Professional Power Amplifiers

 

GX3 | GX5 | GX7

a)  For 4

Ω

 speakers: 350 W – 500 W (program) 

b)  For 4

Ω

 speakers: 550 W – 900 W (program) 

c) For 4

Ω

 speakers: 900 W – 1250 W (program)

Reviews: