Audio compressors and limiters are a kind of specialist hardware used to either amplify the volume of quiet sounds or reduce the volume of loud sounds, by simply compressing the ‚??dynamic range‚?Ě of an audio signal. Audio compression is commonly used during live concerts, broadcasts and studio recording. Audio compressors and limiters, sometimes called a dynamic compressor, can manipulate the volume of sound by alternating the rate of compression through two basic functions ‚?? attack and release controls, which are also able to smooth the final effect of the audio output. There are many different kinds of compressors and limiters available, including very basic models with just a few simple knobs for attacking and releasing, and more advanced models which provide greater versatility when it comes to attenuating audio signals. Audio technicians place an extremely high value on compressors and limiters. An audio limiter is essential for managing the level of audio signals during recording sessions. If the volume produced by a piano for example, is not managed, the recording equipment could easily be overloaded when the pianist plays louder, impacting on the quality of the final recording. Similarly, when the pianist plays at a lower volume, audio compressors and limiters are needed to boost the volume level so that the signal remains consistent throughout. In addition to managing signal levels, compressors and limiters can also be used to create special effects and add an extra dimension to recordings. Audio limiters are able to compress dynamic range audio signals into a much narrower range, hence why they are sometimes called a dynamic compressor. The results of such audio compression include attaining a higher source signal from low volume sound, smooth and consistent tones, an increase in some musical instruments sustain and the ability to enhance the ‚??punch‚?Ě of certain instruments, such as guitars, bass and drums.