AUSTRALIAN MONITOR ACM250 User manual

250W, 6 Channel Mixer Amplifier
ACM250
Description
The ACM250 is a 6 channel, 250 watt mixer amplifier suitable for rack or desk mounting. The
amplifier is a self contained compact unit of solid steel construction.
Inputs
The ACM250 has six universal input channels with separate level controls. Each channel will
accept balanced or unbalanced microphone, line and auxiliary inputs. The unit has industry
standard XLR microphone sockets and dual RCA auxiliary sockets for each channel. Line Input
6 has a lower input sensitivity and is suitable for high level CD players.
Outputs
The ACM250 features 100 volt, 70 volt and 4 ohm isolated transformer outputs, plus a tape
recorder output by means of dual RCA sockets. A balanced 700mV XLR output is also provid-
ed to feed up to 6 power amplifiers.
3 Band EQ
The ACM250 includes a 3 band equaliser (Bass, Middle and High), giving the user a wider
range of tone controls for high level music or difficult voice applications.
Tone Generator
The ACM250 comes standard with an in-built four tone generator module. Tones include Bell,
Pre-announce Chime, Alert Tone (AS2220.1) and Evacuate Tone (AS2220.1). Any of these
tones may be activated from a simple contact closure on the rear panel of the amplifier.
Muting
VOX muting is standard on the ACM250. A mic or line signal on channels 1 or 2 will mute chan-
nels 3, 4, 5 and 6. The muting function can be disabled if via an internal link.
Phantom Power
Phantom Power (18V DC) is available from all mic inputs. A rear panel phantom power on/off
switch is also provided.
Protection
Internal current limiting protects the amplifier from both overload and overdrive conditions.
Australian Monitor Installation Series amplifiers feature a protection network that provides
greater stability and performance. Our amplifiers are recognised
worldwide for their reliability and this is due to the extensive levels of
current limiting which protect the amplifiers from both overload and
overdrive conditions.

Power Output 250 watts RMS
Maximum Load 40 Ohms @ 100 Volts
Power Bandwidth 60Hz - 15kHz < 0.5% THD
Frequency Response 60Hz - 15kHz (± 3dB)
Total Harmonic Distortion 0.5% @ 1kHz rated power
Signal To Noise Ratio -74dB with all controls at their centre position
Tone Controls Bass @ 100Hz: Boost +12dB Cut -12dB; Mid @ 600Hz: Boost +12dB, Cut -12dB;
Treble @ 10kHz: Boost +9dB Cut -9dB
Inputs Six mic/aux universal inputs with XLR female mic sockets and dual RCA Phono aux sockets
Input Sensitivity Mics: 1mV @ 200 Ohms; Aux 1 - 5: 75mV @ 47K Ohms; Aux 6: 300mV @ 47K Ohms
Outputs Speaker: 100, 70 Volts, 4 Ohms; Tape: 350mV @ 10K Ohms; Line: Balanced 700mV
Phantom Power 18 Volts DC on all Mic inputs
Controls 6 Input channel gain controls, 1 Bass control, 1 Mid Control, 1 Treble control,
1 Master gain control, Phantom Power on/off switch (on rear panel)
Indicators Power ”on“ and ”Protect“ LED
Power Source AC 230/240V - 60Hz, 110V - 50Hz (special) 3 pin IEC connector
Power Consumption 400 Watts
Protection Current Limiter protection, plus AC and DC fuses
Dimensions/Weight 88mm H x 480mm W x 330mm D (Chassis Dimensions only). 15kg
Rack Mounting Standard
Tone Generators Built-in four tone generator module.
Includes Bell, Pre-Announce, Alert and Evac Tones
Muting Built-in VOX muting. Channels 1 and 2 will mute channels 3, 4, 5 and 6
Engineered and Distributed By AUDIO TELEX COMMUNICATIONS PTY LTD (ABN 78 001 345 482), 149 Beaconsfield Street, Silverwater, Sydney, NSW, 2128 Australia
NSW Tel: [phone] Fax: [phone] VIC Tel: [phone] Fax: [phone] QLD Tel: [phone] Fax: [phone] WA Tel: [phone] Fax: [phone]
TAS Tel: [phone] Fax: [phone] SA Tel: [phone] Fax: [phone] Export Enquiries: [email protected] Website: www.australianmonitor.com.au
ARCHITECTURAL AND ENGINEERING SPECIFICATIONS
The mixer amplifier shall have six universal inputs each comprising of a balanced microphone with XLR
female sockets and an auxiliary input using dual RCA sockets. A balanced XLR output to drive addi-
tional power amplifiers shall also be provided.
The amplifier master section shall include one master gain control, three EQ controls, one with 12dB of
cut and boost at 100Hz, one with 12dB cut and boost at 600Hz and the other with 9dB of cut and boost
at 10kHz. Speaker outputs shall be transformer isolated at 100 volt, 70 volt and 4 ohms. The amplifier
must be capable of delivering 250 watts RMS into a 40 inductive ohm load, with less than 0.5% distor-
tion measured at 1kHz and with system hum and noise less than -74dB.
The amplifier shall be an Australian Monitor Installation Series model ACM250.