Applications Guide
Crestron
MediaManager™
Amplifiers
The QM-AMP3X80 series of professional power amplifiers has been designed
to provide exceptional audio performance as part of a complete MediaManager
A/V system or anywhere multi-channel amplification is required. Each model
features three high-quality amplifier channels to complement the discrete stereo
program and mono speech output channels of Crestron’s QM-MD7X2
QuickMedia Distribution Center and QM-RMCRX QuickMedia Receiver. The
first two output channels of the QM-AMP3X80MM model deliver 80 Watts per
channel at 8 ohms or 110 Watts at 4 ohms to drive a pair of program
loudspeakers. The third channel delivers 80 Watts at 70 Volts to support
distributed ceiling loudspeakers for speech reinforcement. The QM-
AMP3X80SR model is perfect for multi-zone distributed loudspeaker
applications providing three 80 Watt 70 Volt channels. International versions are
also available featuring 100 Volt outputs (QMI-AMP3X80MM and QMI-
AMP3X80SR). All inputs are balanced with fixed input gain optimized for use
with MediaManager components and other profes4dBu audio
equipment. An efficient Class G power amp topology puts more output power in
less space while generating significantly less heat as compared to conventional
amplifier designs. Each model occupies just one rack space and allows power
control and temperature monitoring via Cresnet using any 2-Series or
MediaManager control system. The amplifiers have a master power switch,
power indicator, and network indicator on the front panel. A switch on the rear
of the unit is provided to bypass the Cresnet controlled power relay, enabling the
amplifier to operate as a standalone unit.
QM-AMP3X80SR Rear View
General Amplifier Specifications
SPECIFICATION DETAILS
Common mode rejection
>70 dB below 1 KHz
Input Impedance
19 K
Ω
balanced, 9.5 K
Ω
unbalanced
Input Sensitivity
1.2 V
RMS
for rated power (80 W / 8
Ω
)
Power Output
80 W into 8
Ω
110 W into 4
Ω
80 W 70 V/100 V outputs
Total Harmonic Distortion
(1KHz)
Less than 0.1% @ 1 W and 75 W into 8
Ω
Less than 0.1% @ 1 W 4
Ω
Less than 0.2% @ 100 W into 4
Ω
Less than 0.1% @ 70/100 V outputs
Frequency Response
20-20 KHz +0 dB / –0.5 dB 4/8
Ω
outputs
100-20 KHz +0 dB/ -3 dB 70/100 V outputs
S/N Ratio
110 dB below rated output power, A-weighted
Power Bandwidth
75 W 20-20 KHz 8
Ω
95 W 20-20 KHz 4
Ω
75 W 100-20 KHz 70/100 V output
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Crestron MediaManager™
Applications Guide – DOC. 6244
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