DSPXmini-FM operational manual V1.2
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Most audio processors use a combination of compression, limiting and clipping to 'funnel' the dynamic range
down, reducing the peak to average ratio in each stage. A cascaded arrangement of compressor, limiter and
clipper produces the best results. The first stage of processing usually operates in a slow manner, the process-
ing getting progressively faster and more aggressive as the audio passes through the chain. The instantaneous
peak clipper or look-ahead limiter is the final stage of the chain and sets the final peak level.
The images below illustrate a section of audio as it passes through a typical audio processor.
The first image to the right is an unprocessed section of audio.
The images that follow represent compression of the input wave-
form, followed by limiting and then finally peak clipping.
Compression
Compression reduces the dynamic range of the audio waveform
slowly in a manner similar to a trained operator riding the gain.
Compression is usually performed on the RMS level of the audio
waveform and the ratio of compression is usually adjustable.
Compression is usually gated to prevent gain riding and suck-up
of noise during silence or quiet periods.
Limiting
Limiting is a faster form of compression that employs faster time
constants and higher ratios to produce a denser sound while
controlling peaks based upon the peak level of the audio wave-
form. Excessive limiting can create a busier packed wall of sound
effect.
Clipping
Clipping the audio waveform will not produce any audible side
effects if performed in moderation. Excessive clipping will pro-
duce a form of distortion that produces a tearing or ripping
sound. Clipping can also be used as an effective method of high
frequency peak control when used in conjunction with distortion
controlling filtering.
