A-SERIES ULTRA LOW NOISE LIMITER FOR LOUDSPEAKER PROTECTION
This design is no longer in production.
LI06 is a PP A-series loudspeaker protection limiter for Modular crossover network type XO01.
The limiter is a high ratio, hard-knee, feedback type with a delay for attack and release to make it's operation almost inaudible.
The attack delay prevents the limiter from reacting on signal peaks, while still retaining a reasonable short attack time.
The release delay holds the limiter's gain reduction until the signal has fallen below the limiter threshold, thus preventing the low-frequency distortion normally seen in limiters with a short release time.
A versatile link system on the module enables the gains of several limiters to track each other either unidirectional or bidirectional.
The limiter's gain, threshold, time constants, link system and LED function are programmed by jumpers on the module.
|Off||The limiter is disconnected from the link.|
|Track||The limiter will track the gainreduction determined by the link signal or, if its own gainreduction is larger than determined by the link signal, it will control the link signal.
Two or more limiters in this mode will always have the same gain.
|Master||The limiter's gain is not controlled by the link signal, however if its own gainreduction is larger than determined by the link-signal, it will control the link signal. If there are more limiters in this mode on the link, the one with the largest gainreduction will control the link signal.|
|Slave||The limiter will track the gainreduction determined by the link signal, but will not control the link signal.|
|Fast||In this mode the LED will light up whenever the signal is above threshold or when the limiter's gain is reduced by 3 dB or more. The LED may flash without the the limiter is reducing the gain (due to the attack delay). This mode is used when it is essential to know when the limiter threshold is reached.|
|Slow||In this mode, the LED will be on when the limiter has reduced the gain by 3 dB or more.|
|Maximum input level||21 dBu|
|THD+N @ 0 dBu input|
|- 20 Hz||< 0.003 % [0.0006 %]|
|- 1 KHz||< 0.003 % [0.0006 %]|
|- 20 KHz||< 0.003 % [0.002 %]|
|THD+N @ 20 dBu input|
|- 20 Hz||< 0.2 %|
|- 1 KHz||< 0.2 %|
|- 20 KHz||< 0.3 %|
|Voltage gain @ 1 KHz||± 0.3 dB [± 0.1 dB]|
|Linearity below threshold||± 0.05 dB [± 0.03 dB]|
|Linearity above threshold||± 0.2 dB [± 0.1 dB]|
|Output noise, RMS||< -106 dBu [-107 dBu]|
|Output noise, CCIR 468-2 Q-peak||[-97 dBu]|
|Output noise, A-wgt RMS||[-110 dBu]|
|Threshold accuracy||± 0.5 dB|
|Ratio, 1 KHz||> 1:250|
|Attack delay (Slow / Fast)||120 mS / 15 mS (program dependent)|
|Attack time (Slow / Fast)||250 mS / 40 mS (program dependent)|
|Release delay (Slow / Fast)||150 mS / 15 mS (program dependent)|
|Release time (Slow / Fast)||200 mS / 20 mS (program dependent)|
|Link tracking||± 0.5 dB|
|Limiter LED turn on level||At threshold, or at gain reduction > 3 dB|
|Supply current (excl. LED)||< 33 mA|
|All specifications subject to change without prior notice.||PP 940831|
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