3.6. 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 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.
3.7. Output connections
The rear panel OUTPUTS section is provided with screw terminal blocks (21), one per channel of
amplification.
The attenuation controls and the output configurations are described later in paragraph 3.8.
The cable which connects the speakers to the amplifier should be high quality and as short and
thick as possible. This is important when covering long distances; For up to 10m we recommend a cable
section not smaller than 2.5mm². For longer distances we recommend 4mm².
ALWAYS USE CLASS 2 WIRING FOR THE SPEAKERS CONNECTION.
Remember that the minimum load impedance for stereo or mono amplifiers is 4Ω. In bridged
mode the impedance must be not less than 8Ω. For a reliable operation under any circumstance connect
lower load impedances than just specified.
Attention: use only the indicated terminals when using the amplifiers in bridge mode.
MPA4-150R
Connect the terminal blocks securely, removing the cable cover 5÷7mm from the end.
CAUTION: The output connectors are HAZARDOUS LIVE.
Be sure to avoid leaving wires exposed. This can cause
short-circuit and risk of electric shock.
MPA6-150R
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