This howto is entirely based on David Taylor‘s excellent Introduction to Audacity youtube lesson. With apologies for the boring soundcheck used in the examples.
Preamble
- Install Audacity and the LAME (.mp3) and and FFmpeg libraries following the instructions from the website.
- Have a mic of some sort ready and plugged into your computer.
- Have headphones ready too.
- If you haven’t done this for a while, re-watch David Taylor’s introduction to Audacity to refresh your memory.
Setup
- Plug in mic and turn it on.
- Open Audacity.
- Decide whether you want to record in stereo or mono (smaller files), using MME, with project rate set to 44100Hz.
- Shut door, turn off fan.
- Mic check – check that audio doesn’t go above -0.0db on the meter.
Recording
- Click record.
- Wait for 3 seconds to capture ambient noise.
- Start speaking – be spectacular.
- Click stop.
Post-production
- Zoom out to see entire clip; zoom in on ambient noise section.
Noise Reduction
Noise reduction gets rid of some of the background hissing and ambient noise to clean up the sound of your recording.
- Select the empty three seconds, then: Effect>Noise reduction
- Click Get Noise Profile.
- Select the entire clip (manually or using Control A then Effect>Noise Reduction. Click preview. If it sounds okay, click okay. It makes a huge difference in the project file, but less of a difference in the final .mp3.
(Note: I think the default settings in Audacity are 17db, sensitivity of 7.5 and frequency smoothing of 7 bands) - Trim off the empty three seconds.
Normalisation
Normalisation brings up the sound levels so that they’re consistent across the recording.
- Effect > normalise. Use -2.0 as standard. (People seem to recommend not going to -0 dB (full volume) because doing so can result in distortion, depending on the settings on the playback device.)
Equalisation
Equalisation can help increase or reduce key frequencies in your recording – for example by getting rid of excessive bass or treble.
- Effect > Equalisation. Click equaliser to show sliders. I used AM radio to reduce sibilance but bought up the treble a bit.
- I tried again using the voice setting but bringing down the treble too. Not sure if I can tell the difference.
Compression
Reduces the dynamic range of the recording (the difference between the loudest and quietest parts) – it can make the audio sound better when it’s amplified.
- Effect > Compressor.
- Uncheck Make-up gain to 0DB and uncheck Compress based on Peaks.
Re-normalisation
- Normalise again to -2.0
Other tweaks
- For any too-heavy peaks or plosives, zoom in and select them, then use Effect > Amplify and reduce the gain for that section.
- Use silence to remove any breaths etc.
Export to .mp3
Export as .mp3 using these settings:
- Export to mono for a podcast
- Constant Bit Rate
- Either 64 (common