Podcast audio postproduction workflow

Podcast audio postproduction workflow.md

Podcast audio postproduction workflow

Here are the steps for podcast episode audio postproduction after recording individual tracks for each participant. The tools I have used:

• Zencastr Professional for recording the podcast
• Audacity for single track editing
• GarageBand for multi track mixing
• Orban Loudness Meter for checking track loudness

1. Postproduction in Zencastr

After the episode has been recorded, click Produce your podcast and select:

• Advanced settings
• Loudness Target: -16 LUFS
• ☑️ Leveler
• ☑️ Noise Gate
• If any of the participants needed to reload the recording view or if they experienced a network break when the recording was ongoing, select ☑️ Separate WAVs. This is needed since there are separate recordings for each uninterrupted recording and they need to be aligned manually. Otherwise, you can postproduce a single WAVE file.

2. Preparation of each single track in Audacity

This step can be skipped if the track has been postproduced in Zencastr or if the participant has used noise or echo cancelling hardware.

1. Check if there's background noise, hiss or echo in the track.
2. Select a silent part of the track -> Effect -> Noise Reduction... -> Get noise profile
3. Select whole track -> Effect -> Noise Reduction... Make sure Noise: Reduce setting is checked. If the noise level is not very dominant, try the default settings:
   • Noise reduction (dB): 12
   • Sensitivity: 6.00
   • Frequencey smoothing (bands): 3 Check the outcome both in the silent and non-silent passages. If there's dominant noise still present, undo the previous step and try noise recution with e.g. the settings 20, 10.00 and 5.
4. I do not recommend echo cancellation unless there's very dominant echoing. Echo cancellation is not as straightforward as noise cancelling and needs much more trial and error. Echo cancellation can be done with Effect -> Noise Gate...
5. Save the edited track in a WAV file.

3. Mix the tracks together in GarageBand

1. Click the downward caret on the right hand side of the beat meter and switch the meter to show only time
2. Import each speech and intro music track separately in GarageBand and name the tracks to help mixing
3. If the speech tracks start in different timepoint, check the individual track lengths to calculate the timepoint where the tracks should start
4. Align and cut each speech track to form the episode content
5. Adjust the volume levels on each track so that they are balanced
6. Tap 'a' on the keyboard to adjust intro and outro music fade in and fade out.
   • About 10 seconds of intro music fade in on top of discussion
   • About 10 seconds of intro music only
   • About 30 seconds of intro music fade out on top of discussion
7. Export the whole episode in a WAVE file via Share -> Export Song to Disk...

4. Check loudness level in Orban Loudness Meter

Select Analysis and click + Button to analyse the exported WAVE file. The target loudness is -16 LKFS (= LUFS). If the analysed loudness is less than -17 LKFS, you should adjust the loudness in Audacity.

5. Set the levels in Audacity

1. Open the exported WAVE file in Audacity
2. Select the whole track -> Effect -> Loudness Normalisation... -> -16.0 LUFS -> OK
3. Audacity will show red markers, if the audio was clipped.
4. If the audio was clipped or is very close to clipping, run Effect -> Limiter... with settings
   • Type: Hard Limit
   • Limit to (dB): -1.00
   • Hold (ms): 10.00
   • Apply Make-up Gain: No
5. Export the file as the final MP3 version: File -> Export -> Export as MP3