Podcasting guide

When making audio recordings, you may notice a background hiss or other ambient sounds (the hum of a computer, a neighbour's lawnmower, air conditioning). Programs such as Zoom or Teams employ live noise reduction to remove these background distractions to leave just your voice. However, this can be quite aggressive and make you sound like you're underwater. Programs such as Audacity allow you to perform noise removal, but this is after you've made the recording - Audacity cannot do it live.

There is a way to remove background noise live using a piece of software called OBS and plugin called VB Cable. Both are free downloads and are available for Mac & PC.

These utilities create a new virtual microphone. It's just like a real microphone and you can choose it as a source in your favourite software such as Audacity or PowerPoint, etc. But what makes it special is that it can have live effects applied to it.

The software is easily installed but it is slightly tricky to set up.

Download and install OBS (Open Broadcast Studio). You may need to ask IT Self Service Portal to do this for you.

Download and install VBCable. Again, you may need to ask IT Self Service Portal.

1. Open OBS
2. Create a new audio source by clicking on the + at the bottom of the Sources panel and selecting Audio Input Capture
3. Give your new audio input a name and select OK
4. Select your device. This could be a built-in mic, the one from your USB webcam or an external USB mic.
5. Your source will be listed in the Sources panel

1. Go to your source under Sources and right click on it
2. Choose Filters
3. Click on the + and choose Noise Suppression
4. You can pick between 2 methods. If you have a reasonably fast PC or Mac, choose RNNoise. For less powerful computers, choose Speex. Speex allows you to vary when the noise removal comes in - the lower the number, the less noise is removed

1. Mute all sources except the device you've created. You can do this by clicking on the small speaker icon. When muted, the icon will turn red with a X next to it. If you want to be able to record desktop sounds (computer bleeps, YouTube videos, etc) make sure Desktop Audio is switched on

2. You may need to increase / reduce the volume of your microphone. To do this, click on the gear icon on your device. Choose Advanced Audio Properties
3. You can increase / decrease the volume in the Volume column
4. Important: For your device, set the Audio Monitoring to Monitor and Output

1. In OBS, pick Settings from the buttons on the right under Controls
2. Go to Audio
3. Go to Advanced
4. Set the Monitoring Device to CABLE Input

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This essentially creates a new, virtual microphone which has noise removal applied to it.

1. In your desired app, e.g. PowerPoint or Audacity, select this new virtual microphone. It will be called CABLE Output or VB-Audio, or some combination.
2. Record as normal.

Please note, you must have OBS open when recording or the virtual microphone will not work.