--- Erik de Castro Lopo <mle+la@email-addr-hidden-nerd.com> wrote:
> You need a low pass filter on the control signal. It
> should
> be somewhere well below 1kHz.
Agreed that you need the filter, but a 'brick wall' at
1Khz means that anything faster then 50ms or so as an
attack time (and there are legit uses for such), will
itself overshoot horrribly due to the gibb effect of
bandlimiting the control signal.
Resampling:
> No it doesn't. You want to absolutely avoid fast
changes in
> the control signal because fast changes will
> modulate the audio signal whcih is **not**
desirable.
So, how do you implement a fast limiter if the fastest
time constant you can have is greater then 1ms?
Remember that to get to within 10 percent of the
computed gain will take multiple timeconstants....
I agree that a 'gain rider' poses no particular
problem at 44.1 or 48K, but even then lowpassing the
audio input to ensure you have the bandwidth to work
in would be a good idea (Think crash cymbal hit).
However for anything fast (and there are well
respected hardware compressors with attack TCs down to
100us), you need substantially more then 44.1 both in
the sidechain and in the gain cell and that means you
need resampling.
Regards, Dan.
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Received on Wed Oct 18 04:15:02 2006
This archive was generated by hypermail 2.1.8 : Wed Oct 18 2006 - 04:15:02 EEST