When a passionate vocalist is belting into a microphone, the tones can be very harsh and unpleasant. But if you know how to get rid of vocal sibilance while recording and mixing, you’ll have a smoother sounding performance.
We know how frustrating it can be to hear that “sss” sound when they sing. If you want to get rid of this problem, there are a few different ways that you can help them out. The first is by eliminating the source of their sibilance, and the other is by reducing it with post-processing so that they are still easily heard. So let’s get started!
1.What is vocal sibilance?
Sibilance occurs when someone pronounces a word with an S or Z and the letter is followed by the “ee” sound, resulting in harsh vocals in an audio mix. If you are pronouncing words like ‘sizzle’ or ‘zoom’, then you might be having problems with sibilance. As they originate from the singer’s mouth, there are some things a singer can do themselves to help get rid of this problem.
Encourage them to Practice singing a word with the letter “s” or “z” followed by an ‘ee’ sound, and repeat it back until they’re sure that the pronunciation is accurate. They should then sing other words in which these letters occur together without getting too caught up on sibilance issues
2. Which part of the frequency spectrum do sibilants occur?
They occur when the consonants are pronounced. The human voice has a range of frequencies. It can be measured in octaves, which starts at 20 hertz (HZ) and goes to 20 khz or kilohertz (kHz). The upper range higher frequencies for any human voice falls around 15 kHz. The frequencies for S and Z are typically between 4000-5000 Hz.
3. Reduce unwanted sounds with a pop filter.
To get rid of unwanted vocal pops and sibilants, get a pop filter. A pop filter is an attachment to a mic stand or handheld recorder, which is designed to reduce unwanted vocal pops and other sounds such as ‘s’ sibilance. Pop filters, or pop shields as they are sometimes called, come in all shapes, sizes and materials. If you want to reduce plosives, then a pop filter can be especially useful. Read more about how to attach a pop filter to a mic stand.
The most common pop filters are made of foam or wire mesh that is stitched onto some sort of fabric to create a shield-like shape for the microphone diaphragm. Other types include circular discs with metal grills on them, which can be put in front of the mic stand.
4. Eliminate sibilance on a vocal track with a de-esser plugin
If you aren’t able to to get rid of sibilance at the microphone stage, you can still deal with harsh sounds using the effects section of an audio mixer post-processing after recording vocals. You can also reduce harsh consonants on a particular vocal track by using a de-esser plugin.
De-essing is mainly used to reduce sibilant sounds such as the “s” sound that can be harsh on your ears when mixed with other vocals or instruments in the frequency range, but it also works for any consonant sounds which are pronounced too sharply.
A de-esser plugin works by using a threshold setting to decide how much of the frequency spectrum needs to be reduced before applying compression. In the de-essing process, the threshold is set so that sounds above it get compressed by an amount determined by the ratio or level settings, and those below are unaffected.
For example, if you had a vocal sound where there was too much “s” sound in your vocal tracks, you might set a threshold of 12 dB below the sibilant. This would mean that any frequency above -12dB (above this point, it’s likely there will be too much sound to compress) and lower than or equal to 0dB will get compressed by an amount determined by your ratio setting.
Various de-esser plugins are available and will work with many different DAWs. Some are free, and others are available for a few hundred dollars. If you don’t want to purchase any plugins, there is also an analog solution that will work with vocals or other instruments. It’s called “sibilance sucking” as it makes the sibilant sound disappear by compressing only high frequencies (above 12dB).
Frank Edwards is the founder and owner of churchsoundtips.com and has over 10 years experience running sound in his local church.