There are lots of reasons why you need to change the volume of your audio in Audacity. A recording might sound too quiet, or some parts louder than others, but luckily you don't have to throw it away and start again.
There are several easy ways you can change the volume of the audio in Audacity, depending on your situation, and below we will show you how.
1. Adjust the Gain Slider
One of the quickest ways to boost the volume is to change the gain slider on the audio track. It's located on the left-hand side of the editing timeline underneath the Audio Track and Mute buttons. By default, the slider is set in the center, but you can move the slider towards the + sign on the right to increase the gain, and move it to the - sign on the left to decrease it.
Changing the slider won't change what the audio looks like in the editing timeline, but you will hear the difference. It also isn't a permanent change, so you can move the slider back to 0 dB at any time to reset the audio gain to its original level.
This method has its limits though; the most you can boost the gain is +36 dB, or -32 dB if you want to reduce it. More importantly, using this method will apply the volume change to the entire track. If you want to adjust the volume of just one selection, you will need to create a new track or try a different method.
Note that audio gain is similar to volume but can mean different things when using a DAW. If you need a quick refresher, read our explanation on gain versus volume.
2. Normalize the Audio
To normalize audio in Audacity, select Effect > Normalize and set Normalize peak amplitude to the level you want. Click the Preview button if you want to check what it sounds like, and click OK to apply the change. Take a look at the screenshot above to see the difference in volume before and after normalizing the audio.
Normalizing a track in Audacity will change the volume to reach a set target. You can use it to increase the overall volume of your audio, or apply it to a collection of different audio files so that they all roughly sound "normal". In other words, there isn't one track that sounds wildly louder or quieter than another.
By default, the Normalize peak amplitude setting is set to -1dB which is a good place to start. In a nutshell, the volume of the entire selection will increase until the loudest part of the audio, also called the peak, reaches the target of -1dB.
Keep in mind that increasing the volume of your audio will also make any background noise in the track louder. This effect works both ways too, so if you want to decrease the volume, set a target that is lower than the peak amplitude (the loudest point).
3. Use the Amplify Effect
The Amplify effect in Audacity can produce the same results as Normalize, but there are some reasons why you would choose this option and not the other. To use this effect, highlight your audio selection and select Effect > Amplify. Once again you have the option to Preview or select OK to apply changes.
Now let's take a look at the options in the Amplify dialogue window. First, there is the option to change the volume of your track using the slider, or if you prefer to enter an exact dB number you can do so as well using the two input boxes.
By default, the first box labeled Amplification (dB) will show you how many dBs you need to increase the volume to reach the target of 0.0 dB. This target is set by the second box labeled New Peak Amplitude (dB) and changing one will affect the other.
All in all, that gives you three ways to change the volume: you can increase the volume by dB's in the first box, move the slider to change the volume, or set a target volume using the second box.
The most important difference between Normalize and Amplify is how it affects the left and right channels of a stereo track. With Normalize, both the left and right channels will be changed independently to reach the target level. With Amplify, however, the volume for the left and right channels is changed by the same amount.
What Method Should You Use?
All three methods will work to increase or decrease the volume of your audio, so which method should you use? While it depends on the situation, there are some general guidelines you can follow.
For a start, the Gain Slider is great for applying small changes in volume to an entire track. But once you start putting more than one audio clip on a track, you might only want to change one particular section. If that's the case, then use Amplify or Normalize to permanently increase the volume of a selection without changing anything else on the track.
Out of the two options, choose Amplify if you want to turn the volume of a track up evenly for both the loud and quiet parts. On the other hand, use Normalize right at the end of your workflow to make sure that your track sounds similar in loudness to other tracks you might hear on Spotify, for example.
There are lots of creative uses for Audacity and as you develop your audio editing skills, you'll learn exactly when to use each method. But for now, knowing how to change the volume will help you produce more polished audio.
If you want to start using Audacity to its full potential, check our guide on how to make music with Audacity at home.
More Than One Way to Change the Volume in Audacity
Changing the volume of the audio is one of the most practical skills you can know when it comes to audio editing. There is more than one way to do it too, each with its own benefits. Now that you know what these volume-changing effects and tools are, you can start mixing your audio for even better results.