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De-esser
9. DE-ESSER
9.1. De-mystifying De-essers
Certain consonant sounds produced by the human voice contain more energy
than others, and have the potential to overload a microphone capsule. This
can produce a disproportionately harsh result when amplified through a sound
system, and/or recorded to analog or digital storage media. The most com-
mon and obvious of these sounds (in English and many languages) is the
"ssss" sound, associated with pronunciation of both "s" and soft "c" conso-
nants, also the consonants "t," "f," "x" and sometimes "d." The technical term
for this particular vocal sound is "sibilance," and the devices that control such
sounds are typically called "de-essers" (or sometimes sibilance controllers).
The frequency range of sibilance will vary depending on the singer/speaker,
the consonant involved, the orientation to the microphone, the microphone
itself, and the normal variations in human vocalization. Cardioid- pattern con-
denser microphones are especially susceptible to sibilance problems, but
the problem can also occur with other types and patterns of microphones. The
range of frequencies affected by sibilance starts above 2 KHz, and generally
Fig. 9a: De-esser
tapers off above 10 KHz; in other words, sibilance is primarily a problem asso-
ciated with higher frequencies (though not the upper octave of human hear-
ing).
9.2. The Sabine De-esser
The Sabine De-esser is essentially a type of frequency-band compressor,
active in the 2-10 KHz range, and inactive below 2KHz and above 10 KHz.
Sabine's algorithm works by dynamically comparing band-specific and asso-
ciated harmonic energy levels to the total signal energy. When spikes are
detected that correspond to sibilance, a shelving filter is imposed on the ap-
propriate frequency bands, and remains in place only for the duration of the
sibilance. High frequency energy levels that remain below the comparison
threshold do not trigger de-essing, and lows and highs outside the sibilance
range are also passed unprocessed and unaffected. This means the Sabine
De-esser is effective but transparent.
9.3. Using the De-esser
Using the Sabine De-esser is simplicity itself. Turning the knob labeled "DE-
ESS CUT" counterclockwise will increase the amount of sibilance reduction,
by increasing the maximum depth of the shelving filter. The maximum allow-
able cut is 24 dB.
31
®
Sabine 2.4 GHz Smart Spectrum
Wireless
LIT-SWM7000-OG-EN-070615.pmd - rr
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