De-essing

A Deesser, also: De - Esser, is an audio effects device or an appropriate software, such as VST plug-in that allows to automatically lower the sibilance contained in a recording of speech or singing ( sibilants ) in the level.

Basics

Is a photograph of the human voice performed is often necessary, for aesthetic reasons to enhance the high frequency components of the housing ( about 7 kHz and 11 kHz ) using an equalizer ( equalization filter ) subsequently. The voice is replaced by a more powerful sound and more of a presence, especially if it is a vocal that has to prevail against musical instruments in the sound of a music recording. But even with pure voice recordings ( radio announcer, radio plays, etc. ) affects a voice thus to most listeners direct and energized at the same volume more attention. A problem arises when lifting the high frequencies of a voice recording: Voiceless sibilants (s, ss, ß, sh, z, tz) consist almost exclusively of such frequencies are reproduced by the strengthening of these areas disproportionately loud. This effect also increases the often applied compression of the speech signal, as though these sounds perceived as loud, from a technical signal levels ago but are low and are unlikely to be lowered from the compressor. Insofar as an edited recording sounds very unpleasant because the sibilance pop out disproportionately loud and very pushy.

Function

A de-esser first disconnects the bottom of the problematic middle and upper frequencies, and subsequently compressed latter, causing it to loud sections automatically in levels are lowered. Subsequently, the two signals are mixed together again. The result is a prominent and well -sounding recording of the human voice, without any annoying sibilance.

It is interesting that some Deesser can be adjusted by means of one-time push of a button or mouse click on male or female voices. The frequency spectrum of a female sibilant different from that of a male. Since this does not always work, a de-esser is preferable with differentiated settings, such as the problematic frequency range.

If a Deesser not in Effektrack available, can be obtained from a conventional compressor with sidechain input and a conventional equalizer even put together a Deesser. The output signal is looped through the equalizer into the sidechain input of the compressor. The settings on the equalizer make this the frequencies of the sibilants are available ( from about 7 kHz lift, the rest lower ) and the compressor, the reduction can be adjusted.

Problems

Exaggerates to the reduction, the sibilants can be completely filtered out. With a voice that can sound as if the singer or the singer abut with the tongue ( lisp ). The effect thus produced can be used for individual voices of a choir singing. With several different in pitch while singing voices only the vocal sounds are relevant. Sibilance are nearly the same pitch and would be multiplied by superimposing, so here can be done in all voices a perfect filtration of sibilance, the sibilance must retain any voice. Applying the technology with individual components (equalizer and compressor with sidechain input ) that you can in this case also the same plosives (P, T, ... ) Filter the voices that can interfere with the homogeneous overall picture of a choir. This also provides more bass, the Equalizer to raise to about 100 Hz. Mutual interference when filtering is not to be expected under normal circumstances, as the sounds are separated in time.