How to Improve Audio Quality in Audacity
Audacity is a free multi-track audio editing software. It’s simple and lightweight but still allows you to do basic recording, editing, sequencing, and FX operations, with a few more advanced features. It’s a great tool for making quick fixes, and to learn the basics of audio production and editing.
Audacity's main features include:
Export/ Import - edit and combine recordings, export in many file formats.
Analysis - Spectrograms and other visualiser for sound analysis
Plug Ins - Support for VST and Audio Unit effect plug-ins. With real-time preview.
Best of all, Audacity is free and you can download it here!
Audacity can help you to improve the quality of your audio in your videos or podcasts. It is important to have high quality audio to not distract the listener from the actual content. Having poor audio quality may result in people switching off your video.
We’ve made this guide to show you how to use Audacity to make professional sounding audio.
Some important effects within Audacity are the Equalizer and Compressor. Understanding how to use these is an important first step in getting better quality audio. Effects in Audacity are located in the top menu.
To use Audacity effects, highlight the selection of the audio you want to process, and select the desired effect from the effect menu. You can hear the difference the effect will make with the “Preview” button. Once you are happy with the settings, press “OK” to render the effect.
The equalizer (Effects > Graphic EQ) is a tool for manipulating the frequency content of sounds, it allows you to set the balance between the low, mid, and high frequencies. Getting your head into how these work will make a huge difference to your audio quality.
Compressors (Effects > Compressor) deal with the loudness and dynamic range of your audio. They can be used to make the “volume” a more consistent level, or prevent sounds from overpowering your vocals.
It’s important to keep the audio level out of the red (below 0db), as this can cause distortion. Use the level control to turn it down. If the distortion was recorded into the audio file, turning down the level will not correct the issue. Unfortunately the inn-built Audacity effects won’t be able to deal with this. You will need to use a de-clipping plugin such as ERA De-Clipper to remove the unwanted distortion.
Let’s look at how to use Audacity to make voice recordings pop.
Ideally you want to start with a good recording by minimising issues throughout the process.
Once you have your vocals in Audacity, open the “Effects” tab from the top menu bar, and select Equaliser.
Use the preview button to monitor the settings and tweak until it sounds clear. Usually a slight cut to the low end (below 120Hz), and a slight high-shelf boost (between 3kHz and). Once you’re happy with the sound, click “OK” to print the changes to your file.
Next, load a Compressor from the same effect menu. Again tweak this until it sounds right. You want to ensure the level of the vocal is consistent, without going too loud or too quiet.
Sometimes it can be tough to get the compressor working properly, especially with something as delicate as a voice. Using a plug-in like the Accusonus Voice Leveller can save you a load of time by simplifying the process and automatically smoothing out volume inconsistencies.
One issue that audio people have to deal with time and time again is background noise. So many good recordings have been damaged by a passing car, blustering wind, or any of the other infinite amounts of noises you didn’t want to hear.
Luckily there are several ways to remove background noise from audio at your disposal.
Audacity has a built in noise remover (Effect > Noise Reduction). This works fairly well in a pinch, but won't help you with all your problems based on its limitations. It captures a noise profile and uses phase/filtering to cancel-out the unwanted signal.
The Noise Remover only works well with certain types of noise As stated in the Audacity manual, the built in noise remover works for “hum, whistle, whine, buzz, and "hiss", such as tape hiss, fan noise or FM/webcast carrier noise. It is not suitable for individual clicks and pops, or irregular background noise such as from traffic or an audience.”
Just as a doctor wouldn’t use an axe to perform brain surgery… the Audacity noise tools won’t fix all your problems.
Using spectrum analysis can help you further determine where your issues are. You can use this to inform you on different frequency areas to automate filtering during different time passages. However, this is a long and convoluted process.
Depending on what noise issues you are facing, there are tools that are designed to combat specific problems more effectively.
For instance the ERA De-Esser is the perfect tool for treating sibilance, hiss, and can allow accurate and specific removal of nuisance high frequencies, without damaging other areas of the sound. The ERA Plosive Remover can help with bumps and mic pops, and tame any low end rumbling and tools like Voice AutoEQ can help make your recordings sound consistent and balanced. Luckily these tools are VSTs so will work in Audacity and other programs.
Whilst Audacity’s stock tool will work for a quick basic fix, to remove background noise from audio, its best to use the right tool for the job to be efficient.
A key concept to understand for video and audio production is Level-Ducking (AKA Sidechain Compression). Utilising this will have a massive impact on the professionality of your videos or podcasts. It will also ensure your voice doesn't get drowned out by other sounds in your productions.
If you have background sound or music playing at the same time as your Vocals, they will be competing for attention. If not mixed well, the music can totally overpower the voice, leaving viewers confused and only getting half the message.
Even if you mix it well, sometimes dynamic changes in the music will still be overpowering.
Audacity has an Auto-Duck effect, which is the perfect tool.
It uses a control track to lower the level of the ducked track. The music will be playing at full volume, then it detects when the narrator starts speaking. This lowers the level of the music track so it is quieter than the narrator. When the narrator finishes, the music returns (releases) to its original level.
In Audacity, the Control Track (Voice/ Narrator) is placed below the track that will be ducked (usually the music/sfx tracks). Mastering this effect can make a huge improvement to the audio quality and intelligibility of your videos and podcasts.