hardlimiters

A hard limiter is a type of electronic circuit or software function that restricts the output signal to a predefined maximum and minimum level. Unlike soft limiters, which gradually reduce the signal as it approaches the limit, hard limiters abruptly clip the signal at the specified boundaries. This means any part of the signal that exceeds the maximum limit is cut off, and any part that falls below the minimum limit is also truncated.

Hard limiters are commonly used in signal processing to prevent overdriving subsequent stages in a system, which can cause distortion or damage. For example, in audio processing, they are used to prevent a signal from exceeding the maximum amplitude that a speaker or amplifier can handle, thereby avoiding clipping distortion. In digital systems, hard limiting can be implemented to ensure that a signal stays within the valid range of digital values.

The primary effect of a hard limiter is the introduction of harmonic distortion, especially when the input signal frequently exceeds the limit. This is because the clipped portions of the waveform are essentially replaced by flat lines at the limit levels, creating sharp transitions that are rich in harmonics. Despite this, the simplicity and effectiveness of hard limiters make them a valuable tool in various applications where absolute signal level control is paramount. They are often employed in conjunction with other signal processing techniques to manage audio dynamics or protect equipment.