COMMERCIAL AUDIO
C
rown’s Commercial Audio mixer/amplifiers deliver legendary Crown quality to the commercial audio
industry. These high-value mixer-amplifiers provide both 4-ohm and constant-voltage outputs (70V
and 100V) for use in a wide range of commercial applications including schools, hospitals, factories,
restaurant/retail, houses of worship, fitness facilities, A/V boardrooms, correctional facilities, and small
offices. Easily configured for a range of uses such as paging, background music, security, and evacua-
tion instructions, Crown’s Commercial Audio units are the smart choice for commercial sound.
SPECIFICATIONS
Performance
Frequency Reponse (at 1 watt from 4-ohm
tap):
70 Hz to 19 kHz ± 1 dB.
Frequency Response (at line out):
20 Hz to 20
kHz ± 1 dB.
Power Bandwidth (at 4-ohm tap, 2 dB below
maxium 1 kHz power):
50 Hz to 20 kHz with
< 0.5% THD
Signal to Noise Ratio (ref. to rated power,
master volume at minimum):
85 dB.
DC Output Offset:
< ±5 mV.
THD:
Less than 0.5% at rated power at 1 kHz.
Input Sensitivity (for full output at maximum
gain):
Balanced mic inputs: 3 mV.
Balanced line inputs: 800 mV.
RCA connectors: 400 mV.
Input Impedance (nominal):
Mic: 400 ohms.
Line: 100 kilohms.
RCA: 50 kilohms.
Crosstalk:
–70dB at 1kHz.
Line Output Level (nominal):
1V into 10
kilohms.
Phantom Power:
15 VDC.
AC Line Voltages Available:
100V 50/60 Hz
120V 60 Hz
220V 50/60 Hz
230V 50/60 Hz
240V 50/60 Hz
Operating Temperature/Humidy:
0° C to 40° C
at 95% relative humidity (non-condensing).
Storage Temperature:
–20° C to 85° C.
Front Panel Controls and Indicators
Power Switch:
Pushbutton on-off switch.
The power switch does not affect the 24V DC
auxiliary power input.
Input Volume Controls:
Microphone/line,
four in 180MA and 1160MA, eight in 280MA.
Detented potentiometers with knobs.
Tone Controls:
Bass and Treble non-detented
recessed potentiometers on each input chan-
nel. Bass ±10 dB at 100 Hz, Treble ±10 dB at
10 kHz.
Power Indicator:
Blue LED indicates power on.
Input Signal Presence Indicator:
Green LED,
one for each input channel, illuminates when
input signal exceeds –24 dBu (line) or –70 dBu
(mic).
Output Signal Presence Indicator:
Green LED,
one for each output channel, illuminates when
output signal level exceeds 100 mV (45 dB
below full power) from the 4-ohm tap. Does
not respond to signals from the AMP INPUT
connector.
Clip Indicators:
Red LED, one per output chan-
nel. Illuminates at threshold of audible distor-
tion. Does not respond to signals from the AMP
INPUT connector.
Output Volume Controls:
One per output chan-
nel. Detented potentiometer with knob.
Back Panel Controls and Connectors
Reset Switch:
Resets the circuit breaker that
protects the power supply. 220/230/240V units
have a fuse instead.
AC Power Inlet:
Detachable IEC.
Auxiliary Power Input:
2-position terminal strip
for 24 VDC (±10%) backup power. Accepts up
to 14 AWG terminal forks.
Amplifier Outputs Connectors:
One per
channel, 4-position terminal strip with COM
(Common), 4 ohms, 70V and 100V terminals.
Accepts up to 14 AWG terminal forks. Non-
touch cover included.
Output VCA Connector:
4-pin Phoenix-type
connector for two VCA control lines of +10 VDC
and ground. Compatible with Crown 1-VCAP
and 4-VCAP modules.
Amp Config Switch:
A DIP switch with two
functions:
1. Assigns an input as the priority input for
each output, thereby temporarily muting the
remaining inputs. Muting is activated by contact
closure.
2. Global enable switch for phantom power.
Does not affect RCA inputs. Default position
is off.
Priority Connector:
3-pin Phoenix-type connec-
tor allows Input 1 or Input 5 (280MA only) to
mute other input signals by contact closure.
Input Routing Switch (280MA only):
DIP
switches that assign each input signal to each
output. Two switches per input.
Line Out Connector:
One 3-pin balanced Phoe-
nix-type connector per output channel. Post
master, pre-VCA. Level controlled by master
volume control.
The tone generator has been omitted. Call
Crown Tech Support if you have a tone genera-
tor question.
Input Connectors:
Mic/Line Connector: 3-pin Phoenix-type, bal-
anced, one per input channel.
Dual RCA Input Connector: For stereo music
signals, unbalanced, summed together, two
connectors per input channel.
Amp Input Connector: 3-pin Phoenix-type,
high-impedance balanced, one per amplifer
channel. Used to link an additional mixer to
the mixer-amplifier. Can be used to connect an
external processor.
Mic/line Switch:
Selects mic-level or line-level
signals. One switch for each balanced input.
Link In/Out Switch:
Slide switch, one per chan-
nel. With the Link Switch IN, any signal applied
to the Amp Input connector will be mixed with
the input signal(s). With the Link Switch OUT,
only the signal from the Amp Input Connector
will appear at the amplifier output.
Cooling
Convection cooled.
Protection
Current Limit Protection:
Included.
Thermal Limit Protection:
Over-temperature
thermal cutout.
DC-Fault Load Protection:
Included.
Included Accessories
Power cord
Detachable rack ears
Screws for rack ears
Non-touch cover for output connectors
Phoenix-type connectors
Spade lugs
Optional Accessories
1-VCAP remote volume control for one channel.
4-VCAP remote volume control for four chan-
nels.
Dimensions
EIA Standard 19-inch (48.3-cm) rack mount
width (EIA RS-310-B) with rack ears, 3.5-inch
(8.9-cm) height and 12.2-inch (31.0-cm) depth
behind the mounting surface (not including non-
touch cover). 4.1 inches (10.5 cm) high includ-
ing feet. 13.9 inches (35.2 cm) deep from front
of knobs to back of non-touch cover.
Weight
Net Weight:
180MA: 21.0 lbs. (9.5 kg).
280MA: 25.3 lbs. (11.5 kg)
1160MA: 25.3 lbs. (11.5 kg)
Shipping Weight:
180MA: 26.0 lbs. (11.8 kg)
280MA: 30.3 lbs. (13.8 kg)
1160MA: 30.3 lbs. (13.8 kg)
Regulatory Certifications
12/07 137964-2B