Information on the Limiter processing block of PowerMatch
Relevant Product(s)
- PowerMatch PM4250
- PowerMatch PM4250N
- PowerMatch PM4500
- PowerMatch PM4500N
- PowerMatch PM8250
- PowerMatch PM8250N
- PowerMatch PM8500
- PowerMatch PM8500N
The PowerMatch limiter provides both peak and RMS voltage limiting for loudspeaker driver protection.
Note: The Limiter block is shown in the processing diagram before the output gain stage, but functionally, the output gain is pre-limiter to provide proper operation.
The limiter may be used as a general purpose peak and RMS limiter. In this application, the peak voltage should be set to prevent over-excursion of the driver, and the RMS limiter should be set to the power handling of the driver; both the peak and RMS values are entered in Volts.
Note: When a Bose loudspeaker preset is active, the limiter settings are specific to the Bose loudspeaker, and the settings are visible but may not be adjusted.
To access the Limiter control panel, double click the block in the Signal Processing View tab for the PowerMatch. The limiter provides peak and RMS limiting, a linking function, and metering for both the gain reduction and output level.
The following controls are available within the Limiter control panel:
EQ Type: Displays the currently selected loudspeaker equalization curve within the Loudspeaker EQ processing block.
Peak Voltage Limiter: The Peak Voltage Threshold defines the behavior of the Peak Voltage limiter and corresponds to the maximum voltage which may be applied to the driver without causing over-excursion. The read-only attack and release times are shown.
RMS Voltage Limiting: The RMS limiter behavior is defined by the RMS Voltage settings: Threshold (V), Attack (msec) and Release (msec).
Link Group: The limiter may be assigned to one of four link groups, or may act independently (no assignment). When channels are linked, the presence of limiting on any of the linked channels engages the limiter on all linked channels.
When Limiters are linked, their signal processing block displays the Limiter Link Group assignment. In the image below, both limiters have been assigned to Link Group 1.
Metering: Meters display the amount of gain reduction, in dB, for both the Peak and RMS limiters. A third meter displays the total gain reduction (the greater of either Peak or RMS), in dB, being applied to the signal. An output gain meter is included to assist in the set up and configuration of the limiter.