Wheezes are high, high-pitched frequencies that occur mainly in the consonants “s”, “sh”, “ch”, and “t”. These can be unpleasant and cause auditory fatigue if not properly controlled. The use of de-essers is an effective technique to reduce these wheezes without affecting the rest of the voice. Below, we explore how to use de-essers to manage wheezing in a vocal track.
Identifying Wheezing
Before applying any processing, it is essential to identify the frequencies where wheezing occurs. These frequencies are usually between 5 kHz and 10 kHz. Listen carefully to the vocal recording and use a spectrum analyzer to locate the wheezing peaks. Once identified, you can proceed to apply a de-esser.
How a De-esser Works
A de-esser is a specific type of compressor designed to reduce sibilance frequencies. It works by detecting problem frequencies and applying gain reduction only when these frequencies reach a certain threshold. This allows precise control of sibilance without affecting the other frequencies of the voice.
De-esser Configuration
To set up a de-esser effectively, follow these steps:
- Insert the De-esser in the Signal Chain: Place the de-esser in the vocal track, usually after the EQ and before the compressor.
- Set the Detection Frequency: Set the detection frequency in the range where the sibilance is found (usually between 5 kHz and 10 kHz). Some de-essers allow you to set a specific band, while others offer wider frequency control.
- Set the Threshold: Adjust the threshold so that the de-esser only activates when wheezing is present. Lower the threshold until you begin to notice an effective reduction in wheezing. Be careful not to set the threshold too low, as this may affect voice clarity.
- Set the Amount of Reduction: Set the amount of gain reduction to control the intensity of wheezing. Start with a reduction of 3 to 6 dB and adjust as needed to obtain a natural sound.
- Listen and Adjust: Listen to the voice in the context of the mix to ensure that the sibilance has been effectively reduced without affecting the tonal quality of the voice. Adjust the detection frequency, threshold and amount of reduction as needed.
Using Additional Equalization
In addition to using the de-esser, you can apply additional equalization to control sibilance. Use a bell curve with a mid-Q to slightly attenuate frequencies in the wheezing range. This can be useful to subtly reduce hiss without aggressive gain reduction.
De-esser automation
On some vocal tracks, the sibilances may vary in intensity throughout the song. Using de-esser automation can help you dynamically adjust the sibilance reduction as needed. For example, you can increase the sibilance reduction in parts of the song where the sibilance is more pronounced and reduce it in other parts to maintain vocal clarity.
Comparison of Different De-essers
There are several de-essing plugins available, each with its own features and algorithms. Some of the most popular include:
- Waves R-De-Esser: A simple and effective de-esser that offers easy-to-use frequency and threshold controls.
- FabFilter Pro-DS: An advanced de-esser with an intuitive graphical interface, offering precise detection modes and flexible reduction options.
- iZotope RX De-esser: Part of the iZotope RX package, this de-esser offers advanced sibilance reduction algorithms and is especially useful in audio post-production.
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Final Evaluation
After applying the de-esser and any additional EQ, listen to the voice in the context of the full mix. Make sure that the sibilances have been effectively controlled without compromising the clarity and naturalness of the voice. Switch between different monitoring systems and listen in different environments to ensure that the voice sounds good in all of them.
Sibilance control is essential to achieve a professional and pleasing vocal mix. By using a de-esser effectively, you can reduce sibilance without negatively affecting the tonal quality of the voice. Complementing this with equalization and automation can help maintain the clarity and naturalness of the voice throughout the song. With these techniques, you can ensure that the vocals in your mix sound clear, balanced, and free of annoying sibilance.