Dynamic Frequency Limiter is a combination of a band- peakfilter / compressor / limiter / transient designer.

The plugin scans a frequency region in the spectrum to find the dB level of this region and use it to dynamically control the volume of the same or another frequency region either (sidechained) ducking, compressing, limiting, enhance transients or everything together at the same time.

In comparison to normal compressors/limiters, which compress the whole signal or a wide band, this compressor uses biquad filters to apply the gain reduction/addition needed even if the bandwidth is just a single frequency (e.g. using it as a feedback destroyer).

The cutoff frequency and bandwidth of both the scanning of a region and the alteration of a region can be independently controlled or linked together.

The compression part of the plugin contains all the normal controls for a compressor: threshold, ratio, attack, decay, gain, which meaning should be known to all. Though, the threshold is applied to a band-filtered signal, reading the amplitude of only that frequency region. Then goes through a delay, envelope follower and clipper to calculate the gain reduction, which is then applied to a biquad peak filter. Also, the gain is not applied to the whole signal, but is added to the peak-filter's gain. Using the make-up gain (adds the inverted threshold dB to the gain) or gain knob a sustain function for a certain frequency region is created. Using short attack&release values this can make up some wild, dynamic distortions.

Using the transient knob, the attack stage becomes a transient designer. This part isn't delayed by the envelope-delay. So combining these can create a LOT of punch! Also adding boost and grid when using the plugin as a distortion.

Using the exaggerate button, the compressor ratio is multiplied by 2, creating a ducking effect when the signal surpasses the threshold amount. Combined with the transient knob, this allows for fully accentuating drum punch/hit while ducking the sustain part at the same time.

A delay on the envelope allows you to delay the gain reduction, to allow the passage of a short burst of sound before the compression kicks in.

The internal routing ends with a simple hard limiter to protect your dear speakers. Only the release time can be adjusted and the threshold is 0dB (maximum loudness)

Uses can be:

Removing (compressing/limiting) annoying peaks in a certain frequency region without altering the volume of other regions in the spectrum.
Feedback destroyer.
Creating peak-controlled resonances.
Shaping the overall envelope of sounds (excellent on both drums and synthesizers).
Leaving a frequency region through, while blocking another.
On short attack/decay times, all kinds of (very nasty) shapable distortions can be created. Combined with the sidechain functionality this can create lots of interesting effects.
Maximizing loudness/sustain of a frequency region.
Overall soundsculpting.
Sidechaining by another channel to induce sound effects ranging from simple compressing/ducking, resonating, expanding frequency regions, dynamic distortions to audiorate AM modulation.