Rane MA 4, Instruction Manual

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Manual-2
Description & Operation
• Each channel delivers 100 watts of power into a 4 or 8Ω load (constant power).
º Average load impedance is estimated, then used to set the limiter to confine the maximum average power to 100 watts.
• Universal voltage , power-factor-corrected power supply (see figure on data sheet).
º Switch-mode power supply operates 100 to 240 VAC, 50 Hz or 60 Hz.
º Under- and over-voltage protection with inrush current management.
º The power supply features an IEC appliance inlet.
º Must be connected to a grounded mains socket-outlet.
• Class D amplifiers operate at up to 85% efficiency.
º Amplifiers operate in floating Bridged configuration.
º Channels are not bridgeable .
º Balanced Inputs 22 dBu maximum.
• Rear panel SENSITIVITY controls allow continuous adjustment from +22 dBu to +4 dBu.
º Integrated Limiter prevents clipping regardless of input level and sensitivity setting with input levels up to +22 dBu.
º The best dynamic range is achieved when all stages in a system clip at the same time. If the signal processing in front of the ampli-
fier clips at +22 dBu, and the amplifier sensitivity is set so that it clips at + 4 dBu, you loose 18 dB of headroom.
• REMOTE DC LEVEL control inputs are provided for each channel.
º Audio taper attenuation with external linear pot (0 dB to –80 dB, –16 dB at center position).
º Clickless mute with switch (use SPST switch; connect Vc to GND to mute).
º Euroblock connector with strain relief (Vref, Vcontrol, GND).
º One pot may control all four channels by daisy-chaining the Vc of the used port to the other three ports.
• The Load-dependent Limiter eliminates voltage and current clipping, ensuring signal integrity and uninterrupted service.
º The peak signal detector for the Limiter is oversampled to insure accuracy at any frequency.
º Instantaneous attack and 3 dB per second decay.
• Average load impedance is estimated and used to determine the Limiter threshold setting.
º The front panel Load indicator (see metering) indicates the load status.
º The normal impedance range is 2 to 16 Ω. (green Load indicator on ).
º Average load impedance is estimated over 180 ms and requires a minimum of 3.3 watts averaged over 180 ms .
• A s oft-knee COMPressor is enabled ( down ) or disabled ( up ) for all channels using the rear panel dipswitch.
º The rms threshold is 10 dB below the Limiter threshold.
· Allows full uncompressed operation of typical program material while reducing continuous sine wave power.
· Soft knee span is 10 dB; Ratio is 3:1; Attack is 1.5 seconds; Decay is 3 dB per second.
º If the internal amplifier temperature goes above 65˚ C, the compressor is automatically set to the 10 dB setting until the
temperature drops below 55˚ C. At normal operating temperatures, the threshold setting follows the dipswitch setting.
• Downward EXPander reduces noise in the absence of signal.
º The expander is enabled ( down ) or disabled ( up ) for all channels using the rear panel dipswitch.
º Threshold is –70 dBFS; Ratio is 3:1; Attack time is 50 ms; Gain reduction 10 dB per second.
• 20, 40, 60 or 80 Hz HIGH-PASS filters are selected using the rear panel dipswitch.
º Setting affects all channels.
º Filters are 12 dB per octave, Butterworth alignment.
MA 4
100-240V
50/60 Hz 500 WATTS
RANE CORP.
Class 2 Wiring
OUTPUTS
Active Low Use Rane VR 2 or 20 k Ω pot
HIGH-PASS
20Hz
40Hz
60Hz
80Hz
ON
4
+ – + – + – + – + – + – + – +
REMOTE LEVEL 4
4 FLAG 3 2 1
FAULT
Vr Vc Vr Vc Vr Vc Vr Vc
–
+ – + – + – + – + – + – + – + –
3 2 1
MASTER
SLAVE
COMP
4 3 2 1
1 2 3 4
+ – + – + – + –
Vr Vc Vr Vc Vr Vc Vr Vc
+ – + – + – + –
INPUTS MODE
13
22
dBu
SENSITIVITY
4
3
13
22
dBu
SENSITIVITY
4
2
13
22
dBu
SENSITIVITY
4
1
13
22
dBu
SENSITIVITY
4
EXP ON
3
INT EXT
LOAD
2
INT EXT
LOAD
1
INT EXT
LOAD
4
INT EXT
LOAD
COMMERCIAL AUDIO
EQUIPMENT 24TJ
R
FOR CONTINUED GROUNDING
PROTECTION DO NOT REMOVE
THIS SCREW.
MA 4
ACN 001
345 482
100-240V
50/60 Hz 500 WATTS
MADE IN U.S.A.
RANE CORP.
Class 2 Wiring
OUTPUTS
Active Low Use Rane VR 2 or 20 k Ω pot
HIGH-PASS
20Hz
40Hz
60Hz
80Hz
ON
4
+ – + – + – + – + – + – + – +
REMOTE LEVEL 4
4 FLAG 3 2 1
FAULT
Vr Vc Vr Vc Vr Vc Vr Vc
–
+ – + – + – + – + – + – + – + –
3 2 1
MASTER
SLAVE
COMP
4 3 2 1
1 2 3 4
+ – + – + – + –
Vr Vc Vr Vc Vr Vc Vr Vc
+ – + – + – + –
INPUTS MODE
13
22
dBu
SENSITIVITY
4
3
13
22
dBu
SENSITIVITY
4
2
13
22
dBu
SENSITIVITY
4
1
13
22
dBu
SENSITIVITY
4
EXP ON
3
INT EXT
LOAD
2
INT EXT
LOAD
1
INT EXT
LOAD
4
INT EXT
LOAD
COMMERCIAL AUDIO
EQUIPMENT 24TJ
R
FOR CONTINUED GROUNDING
PROTECTION DO NOT REMOVE
THIS SCREW.
4 3 2 1
ON
4 3 2 1
ON
MA 4
ACN 001
345 482
100-240V
50/60 Hz 500 WATTS
MADE IN U.S.A.
RANE CORP.
Class 2 Wiring
OUTPUTS
Active Low Use Rane VR 2 or 20 k Ω pot
HIGH-PASS
20Hz
40Hz
60Hz
80Hz
ON
4
+ – + – + – + – + – + – + – +
REMOTE LEVEL 4
4 FLAG 3 2 1
FAULT
Vr Vc Vr Vc Vr Vc Vr Vc
–
+ – + – + – + – + – + – + – + –
3 2 1
MASTER
SLAVE
COMP
4 3 2 1
1 2 3 4
+ – + – + – + –
Vr Vc Vr Vc Vr Vc Vr Vc
+ – + – + – + –
INPUTS MODE
13
22
dBu
SENSITIVITY
4
3
13
22
dBu
SENSITIVITY
4
2
13
22
dBu
SENSITIVITY
4
1
13
22
dBu
SENSITIVITY
4
EXP ON
3
INT EXT
LOAD
2
INT EXT
LOAD
1
INT EXT
LOAD
4
INT EXT
LOAD
COMMERCIAL AUDIO
EQUIPMENT 24TJ
R
FOR CONTINUED GROUNDING
PROTECTION DO NOT REMOVE
THIS SCREW.
4 3 2 1
ON
4 3 2 1
ON