Peak Limiter is the first Airwindows loudness plugin, and has a number of unique features. While these days I encourage people to not limit or distort, and to use ADClip for the cleanest possible handling of overs, and to get NC-17 if you’re looking to just do silly loudness… there have been other approaches from Airwindows in the past.
Peak Limiter has three controls: boost amount, corner frequency and distortion.
Boost amount is obvious, offering 12 db of gain on tap. Corner Frequency isn’t at all obvious—what it’s doing is, sending a highpassed signal to the boost and the peak limiter, and then passing through what’s under the cutoff straight to the output. The idea was that you could push loudness while still having sine basses or something, and have them combine without distorting the bass. It sort of worked… and then Distortion is exactly what it would appear to be. Plus, it’s tracking overshoots and chasing them with a Chebyshev filter much like what NC-17 does.
The whole thing works like this: splitting of frequencies to clean up the bass, compression kicking in to handle the added gain, second harmonic added to supplement the lows: merge to an output, apply the soft-clipping of Distortion and then hard-clip after that just to be sure.
If you’d like a copy of Peak Limiter, buy one of the Airwindows loudenation plugins (NC-17 or ADClip, which clips much better than Peak Limiter ever will) and email me. I’ll send it.