QSC Audio CX Series - Manual (Page 5)

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II. Overall Description
The CX Series from QSC comprises six high-efficiency professional power amplifier models, each with two
independent channels. The table below lists the range’s audio power ratings.
Each channel has its own power transformer secondary. The CX4, CX4T, CX6 and CX6T utilize complementary
Class AB linear output circuitry. For improved efficiency, the CX12 and CX12T utilize Class H step linear
complementary output circuitry and have bipolar multi-rail power supplies. The power transformers, as are the
output transformers, are mounted in the front of the amplifier chassis, as close to the front mounting rails as
possible; this keeps the unit’s center of gravity forward to minimize the twisting force on the front
mounting ears. Still, the amplifier should be supported at all four corners, especially if it is in a
portable rack.
The CX4 and CX4T are two rack spaces high; the CX6, CX6T, CX12, and CX12T are three rack spaces
high. The adjacent table lists the amplifiers’ weights by model.
The amplifiers require a rack depth of 18 inches (45.7 cm) to clear the rear support ears. Allow
some additional clearance for input and output connectors at the rear panel, which is 16.9 inches
(42.9 cm) behind the plane of the frount mounting rails. The built-in cooling fan draws air in at
the rear of the chassis and exhausts it through vents in the front panel. The flow-through cooling
scheme allows you to rack-mount the amplifiers one atop the other, with no clearance necessary
in between. This mounting technique also helps support the weight of the upper amplifiers.
The CX Series derives much of its design from our award-winning MXa Series amplifiers. They are engineered
for stability and exceptional reliability, with protection for open or short circuits and mismatched loads. To protect
your loudspeakers, the outputs mute during turn-on and turn-off, and also in the event of a DC fault. The CX4
and CX4T are AC coupled and cannot pass DC to the load. Therefore, the DC fault muting is not required. All
protection circuitry automatically resets to normal when conditions assure safe operation.
Every CX amplifier features thermal management and protection in the form of a two-speed fan and extruded
aluminum heat sinks with direct-mounted output devices. If a heat sink overheats to 85½ C or higher, a protection
circuit mutes the amplifier channel output.
MODEL NET WEIGHT
CX4 13.6 kg; 27 lb
CX4T 18.2 kg; 37 lb
CX6 20 kg; 42 lb
CX6T 25 kg; 55 lb
CX12 22.7 kg; 50 lb
MODEL 8
Ω Ω Ω Ω Ω
1 4
Ω Ω Ω Ω Ω
1 2
Ω Ω Ω Ω Ω
2 25 volts 3 70 volts 1 100 volts 1
CX4 150 watts 225 watts 350 watts
CX4T 150 watts 225 watts 350 watts 150 watts 4 175 watts 4 175 watts 4
CX6 200 watts 300 watts 450 watts
CX6T 200 watts 300 watts 450 watts 200 watts 3 250 watts 3 250 watts 3
CX12 425 watts 600 watts 900 watts
CX12T 425 watts 600 watts 900 watts 400 watts 3 500 watts 3 500 watts 3
1: FTC watts per channel, 20 Hz–20 kHz, 0.1% THD
2: EIA watts per channel, 1 kHz, 1% THD
3: Watts per channel, 45 Hz-15 kHz, 0.25% THD
4: Watts per channel, 50 Hz-15 kHz, 0.25% THD