Exciter

An Exciter is an audio signal processing technique used to enhance a signal by dynamic equalization, phase manipulation and harmonic synthesis of (usually) high frequency signals. Dynamic Equalization involves variation of the Equalizer characteristics in the time domain as a function of the input. Due to the varying nature, noise is reduced compared to static equalizers. Harmonic synthesis involves the creation of higher order harmonics from the fundamental frequency signals present in the recording. As noise usually decreases with the frequency band, the harmonics are derived from a purer frequency band resulting in clearer highs. Exciters are also used to synthesize harmonics of low frequency signals to simulate deep bass in smaller speakers. Originally made in valve (transistor) based equipment, they are now implemented as part of a digital signal processor, often trying to emulate analogue Exciters. Exciters are mostly found as plug-ins for sound editing software and in sound enhancement processors.

Uses

 * Unlike traditional equalization, exciters have much better noise characteristics which make them highly useful in enhancing dull recordings.


 * Exciters are also used for restoring old recordings by adding lost spectral content


 * Exciters are increasingly implemented as an audio enhancement for hardware and software media players


 * Exciters can be useful for vinyl DJs to improve sound quality of the set.