compressorexpander

A compressor expander is a type of audio signal processing device or software that performs both compression and expansion on an audio signal. Compression reduces the dynamic range of a signal by decreasing the level of sounds that exceed a certain threshold. Expansion, conversely, increases the dynamic range by increasing the level of sounds that fall below a certain threshold, or by decreasing the level of signals that are already below a threshold, effectively making quiet sounds quieter.

These devices are often found in music production, live sound reinforcement, and broadcasting. In a single unit, a compressor expander allows for precise control over the overall loudness and perceived impact of an audio source. For example, a producer might use the compression portion to even out vocal levels, making them consistently audible. Simultaneously, the expansion portion could be used to subtly reduce background noise or "bleed" from other instruments when the main signal is not present, creating a cleaner and more focused sound.

The parameters for both compression and expansion within a single unit typically include threshold, ratio, attack, and release times, similar to standalone compressors and expanders. The threshold determines the level at which the processing begins. The ratio dictates how much the signal is compressed or expanded. Attack and release times control how quickly the processing engages and disengages. By combining these two distinct processes, a compressor expander offers a versatile tool for shaping the dynamics of audio signals.