Appendix I: Limiters and How to Set Them Correctly
Your amplifier has two levels of dynamic protection on its outputs — a traditional program
limiter, and a peak limiter.
Program Limiter
High performance digital limiters are provided for each output with control over attack time,
release time and threshold parameters. This level of control allows the user to balance the
required subjective quality of the limiter against the driver protection requirements. It does
also mean that an incorrectly set limiter may sound awful!
In particular (as with all limiters) using too fast an attack or release time for the type of signal
in the pass-band will result in excessive low frequency distortion. There is provision, within
the remote software application, to set automatic limiter time constants. Use this option if
you are unsure how to set the time constants manually. We recommend the use of the
automatic setting.
In this mode the time constants will be automatically set from the corresponding channel’s
High-Pass filter frequency according to the table below.
High Pass Filter Auto Attack Time Release Time
<10Hz — 31Hz 45mS x16 (720mS)
31Hz — 63Hz 16mS x16 (256mS)
63Hz — 125Hz 8mS x16 (128mS)
125Hz — 250Hz 4mS x16 (64mS)
250Hz — 500Hz 2mS x16 (32mS)
500Hz - 1kHz 1mS x16 (16mS)
1kHz — 2kHz 0.5mS x16 (8mS)
2kHz — >32kHz 0.3mS x16 (4mS)