3
EN
WELCOME
Thank you for purchasing a QSC Audio amplifi er. The GX Series is 
the latest in a long line of hard-working, low cost amplifi ers, designed 
to produce the best possible results for a wide range of users. In 
most cases, you can plug and play with no surprises, but for best 
results, we recommend you review the enclosed user guide.
UNPACKING
Confi rm that the amplifi er has no visible shipping damage. Confi rm 
that amplifi er has the correct AC cord and voltage rating for your 
region (See rear panel, Serial Number plate). It is best to keep the 
carton in case the amplifi er needs to be returned, at least until it has 
been tested.
SUPPORT AND SERVICE
QSC Audio Products maintains a world-wide network of distributors 
and service centers. These local agencies will be able to answer your 
questions and take care of any problems.
QSC WEBSITE
Our website, www.qscaudio.com, is factory-maintained and 
supported in multiple languages. Visit frequently for new 
announcements, typical questions, and other user information.
IMPORTANT SAFETY PRECAUTIONS
QSC products are designed for safe operation, and have been 
certifi ed by recognized product safety agencies to meet all normal 
standards for this type of product. However, dangerous voltages 
and power levels exist within the covers of this amplifi er. The user 
is requested to study the precautions in this manual. If the product 
has been dropped, dented, soaked, or appears to have loose parts 
inside, the risk of shock is increased. Unplug the AC cord, and take 
the product to qualifi ed service personnel for inspection and repairs.
POWER RATINGS
Watts at 0.1% clipping, both channels driven
Model
8 ohms 4 ohms 2 ohms*
GX3 300 425 200
GX5 500 700 350
GX7 725 1000 600
*NOTE: 2-ohm loading is not recommended for high power use. 
To avoid protective limiting, use only at low levels.
FEATURES
Power levels matched to the most popular speakers used by 
entertainers.
Optimized for maximum real-world headroom into 4Ω and 8Ω 
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 (only 10.1” / 257 mm) fi ts in compact, 
inexpensive effects racks.
Light weight – less than 26 lbs (12.5 kg).
Detented gain controls for precise setting and matching of 
sensitivity.
GuardRail
 
 automatically protects the amplifi er 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.
GX POWER AMPLIFIER SERIES
Professional Power Amplifi ers