9
3.6. Input options
1 mono
4 mono amplifiers for 4 different mono signal
2 mono
4 mono amplifiers for a common mono input
3 mono
4 mono amplifiers for a common stereo input
4 stereo
2 stereo amplifiers for 2 different stereo inputs
5 stereo
2 stereo amplifiers for a common stereo input
6 bridged
2 bridged amplifiers for 2 different mono signals
7 bridged
2 bridged amplifiers for a common mono signal
8 bridged
2 bridged amplifiers for a common stereo signal
9 combination 1 bridged amplifier and 2 mono amplifiers for a common mono input
10 combination 1 bridged amplifier and 1 stereo amplifier for 2 different stereo inputs
11 combination 1 bridged amplifier and 1 stereo amplifier for a common stereo input
INPUT SIGNALS
INPUT SELECTORS
MODE ST-BR
N.
1 2 3 4
CH1
CH2
CH3
CH4
CH1-2 CH3-4
1 I1 I2 I3 I4
IN1
IN2
IN3
IN4
ST
ST
2
I
-
-
-
IN1
LINK CH1
LINK CH1
LINK CH2
ST
ST
3
L
R
-
-
IN1+IN2
LINK CH1
LINK CH1
LINK CH2
ST
ST
4 L1 R1 L2 R2
IN1
IN2
IN3
IN4
ST
ST
5
L
R
-
-
IN1
IN2
LINK CH1
LINK CH2
ST
ST
6 I1 - I2 -
IN1
-
IN3
-
BR
BR
7 I - - -
IN1
-
LINK
CH1
-
BR
BR
8 L R - -
IN1+IN2
-
LINK
CH1
-
BR
BR
9
I
-
-
-
IN1
LINK CH1
LINK CH1
LINK CH2
BR
ST
10 L1 R1 L2 R2
IN1+IN2
-
IN3
IN4
BR
ST
11
L
R
-
-
IN1+IN2
IN2
LINK CH1
LINK CH2
BR
ST
3.7. Limiter circuit
This system is an always active protection inside the MPA R series of amplifiers. The ANTICLIP
circuitry constantly analyses harmonic distortion caused by excessive signal excursion at the power
amplifier's output and automatically reduces the input level in order never to reach distortion. The
MPA4-400R amplifiers are delivered with the anticlip system adjusted at a threshold of 1% THD (hard
limiting). However, this value can be switched to a softer limiting (5% THD) via an internal jumper (see
diagram).
The great convenience of such a circuit in any kind of installation has to be remarked: The clear
advantage of a limiting system in front of conventional compressors is that the former does practically not
alter the dynamic range, acting only when the distortion threshold is reached.
CAUTION: Changes on the ANTICLIP configuration have to be performed by a qualified
technician.
