Audio

A guide to vocal compression for podcasters

A guide to vocal compression for podcasters

Written by Miles MercerSocial Media Coordinator2022.03.10

There you are, listening back to the recording of your latest interview when, all of a sudden, your guest begins to laugh. You reach for the volume button to turn it down, but a few moments later they speak so softly you can barely hear them, and you have to reach for the volume button once more. 

While the volume of one’s voice isn’t always easy to control, there is an essential piece of podcast editing that will help you overcome these challenges and achieve a well-balanced finished product. It’s called compression.

Single-band compressor plugin in Adobe Audition

If you get tired of adjusting the volume every time there is a loud or soft passage in your podcast, a compressor plugin is a piece of software that can do this for you. However, because it doesn’t have ears like we do, you’ll first need to feed the compressor specific information so it knows how to respond to the audio it’s being fed, and adjust the volume accordingly. 

This information comes in the form of four instructions: Threshold, Ratio, Attack, and Release. 

Threshold is expressed as a decibel (dB) level and will tell the compressor to turn the audio volume down when it reaches a certain level. For example, if the threshold is set to -10dB and the audio reaches -8dB, the compressor will begin to turn the volume down. In order to find the ideal threshold level, identify the average volume of your audio and set your threshold level 1dB below that. This will create a very gentle ‘squeeze’ on your normal speaking voice that will soften peaks.

Ratio is the instruction that tells your compressor how much to turn the volume down by when the threshold is hit. It’s commonly expressed as 1:1 (uncompressed), 2:1, or 4:1. For example, if our threshold is set to -10dB and the audio reaches -8dB, that means there’s a 2dB difference between the actual audio and the threshold. With a 2:1 ratio, that 2dB difference becomes 1dB, and the actual audio level will be reduced to -9dB instead of the original -8dB. Depending on how much the volume in your podcast varies, you may want to experiment with your ratio value to achieve the most natural-sounding finished product. A 4:1 ratio is often the most reasonable to achieve the desired effect.

Expressed as time, attack is the amount of time it takes the compressor to turn down the volume once it hits the threshold. An attack of 3-5ms is typically used on voices.

Also expressed as time, release is the amount of time it takes the audio to return to its original level after the compressor hits the threshold. This is usually set at around 100ms.

Compression tends to decrease overall volume so, once you’ve achieved the desired balance in your mix, remember to add a little bit of gain to your final audio final to bring it back up to its original level. 

While compression is an important tool to have in your kit, it’s best used sparingly and lightly so as to not erode the natural dynamics in your voice. If you can master this concept, you’re one step closer to having that clean and professional sound you’re looking for. 

Where to find compressor plugins

First, check the stock effects in whichever Digital Audio Workstation (DAW) you use. Most DAWs will have a simple compressor including all of the parameters discussed above. 

However, if you want to dip into the world of third-party plugins, here are a few affordable and effective suggestions:

Waves CLA-2A Compressor/Limiter

Modeled on a legendary tube compressor, this plugin will give your vocals a vintage warmness.

Lindell Audio 7X-500

A classic interface with some modern features that will allow you to dial in a range of different sounds and styles. Comes with a 14-day free trial if you want to try before you buy.

Arturia Tube-STA

Based on a legendary valve compressor of the early broadcast and recording era. A timeless sound that will always be in style.