Sibilance occurs – to one degree or another – in just about every vocal track you’ll ever record, and it’s something you should be on the lookout for as too much sibilance in a track can be extremely distracting to a listeners. Here we’ll look at exactly what sibilance is, and also at a couple of methods of getting rid of it.
What is Sibilance?
In its simplest terms, sibilance is the harsh sounds produced by certain consonants; the most common perpetrators are S, T and Z sounds. Technically speaking, the sounds associated with these letters produce disproportionate dynamics in certain upper midrange frequencies. Put another way, these sounds “pop” (and sometimes hiss) by being much louder at higher frequencies, which become very noticeable in recordings.
What It is Not
First, it should be noted that the appearance of sibilance will be negligible in many singers. The typical line of advice is that if it’s not distracting from the overall vocal track, you likely want to avoid doing anything to the track as it might harm the rest of the track. It should also be noted that the extent that this particular advice should be adhered to changes slightly as your mixing expertise grows.
Additionally, this is not something that you should try to control from the standpoint of having the vocalist sing differently. Sibilance is not a vocal problem, it is a natural part of human speech and therefore human singing.
There are basically two ways to control sibilance:
1. Get Rid of It at the Source
Again, this doesn’t mean telling your singers to change the way he or she forms words. However there are a few things you can do, including moving the vocalist away from the mic. Close-miking techniques on vocalists have produced some great records (see pretty much the entirety of the Elliot Smith discography), but it just doesn’t work for everyone’s style. Obviously, the cure for this is to move the microphone back a bit to cut down on sibilance.
Another note is that pop filters, while great for stopping those “P” and “B” sounds (among others), don’t typically help with sibilance. So while you should still (almost) always use one, don’t use it for the purposes of helping with sibilance.
2. Get Rid of It in the Mix
Because sibilance is so prevalent, many techniques have been developed in the mixing phase to cut down on it. A de-esser is an audio processor developed purely to get rid of sibilance.
A de-esser essentially works by applying certain compression, gain reduction and EQ settings to a very narrow frequency band designed to eliminate sibilance. Many of today’s DAW software packages have a de-esser or a compressor with specific de-esser settings. Just be sure to play around with the settings until you discover what will best help you on your specific track, since all problems will be different.
A final note: be sure not to over-compress tracks with sibilance problems. This can lead to making the problem even worse by accentuating it. Because of this, you’ll typically want to take any de-essing steps before you begin compressing the track.