User manual

Page 36 User manual P1 Audio Processor
The P1 limiter with dynamic threshold control
Considering that almost half of the processing power in the P1 is
dedicated to the limiter, it doesn’t exactly have a high profile on the
front control panel, so what’s it all about? Let’s start with the basics;
All digital recording systems have a maximum signal level which they
can handle. If you go above this level then digital audio clipping will
result and it sounds truly awful. Not only are the peaks and troughs
of the audio waveform clipped (as shown below) but a second
problem called aliasing distortion can occur which is even worse.
A limiter allows the maximum audio
level to be fixed to a level set by the
limiter threshold. So any audio which
comes in above that threshold is gain
reduced to be no higher than the
threshold setting. Have a look at the
‘before and after’ audio waveforms
below. Note that some of the audio
peaks which were above the limiter
threshold are not, after limiting, exactly
on the threshold but below. This is
due to the release time of a limiter and
is a necessary and desirable limiter
characteristic.