Audio-Recording & Audio-Editing with Audacity

bit.ly/mmcl-audacity

Google Drive assets folder

Learning Outcomes

1. Understand physics of sound
2. Understand universal practices of sound recording
3. Be familiar with common functions within Audacity

Contents

Part 1: Audio Recording

1. Understanding the science of sound

• What is sound?
• Sound waves ___ energy over time/space
• Sound waves often reflect
  • Echo vs Reverb: Example clip
  • Most reflective things?
  • Solution(s)?

2. Knowing the conventions of recording tools

• Loudness measured in decibels (dB)
• Relative scale: 0 dB is threshold of clipping (distortion)
  • Ideal recording range (primary audio): -12 dB (+/- 3 dB)
• Volume vs Gain
• Input (recording) vs Output (playback) volume/gain
  • Increased input volume/gain = increased ___

3. Understanding channels

1. Channel: Digital/physical pathway for (unique) sound to travel
   • Input: Device
   • Output: Side/direction
2. Mono vs Stereo vs Surround
   • Potential maximum number of channels (not always actual number)

4. Knowing microphone types

• Audio Equipment loanable through MMCL
• MMCL Audio Equipment tutorials

1. Wearable: Transmitter(s) (TX) + Receiver (RX) with/without lav (lavalier) AKA lapel mics
   • How? Near collarbone (sometimes hidden from camera)
   • Who? One person
2. Mountable (close): Mounted on stand or handheld mic
   • How? Within one or two hand-lengths
   • Who? One or more persons within arms-length
3. Mounted (distant): Shotgun/boom mic
   • How? Mounted to overhead pole
   • Who? One or more persons beyond arms-length

5. Knowing recording functionality & patterns

• Dynamic vs Condenser (Rode, 2022)
  • Condensers mics more sensitive (production studios/sets)
• Shape of mic and size/position/number of grills (Rode, 2015)
  • Cardioid: Heart shape
  • Omni-directional: Circle shape
  • Bi-directional: Number 8 shape
  • Other variations
• Some mics have changeable patterns

6. Knowing cables/adapters

• USB: USB-A, USB-C, Micro-USB
  • To computers, smartphones, some standalone recorders
• 3.5 mm: TRS (one-way travel for sound) vs TRRS (two-way travel for sound)
  • To video cameras, standalone recorders, wireless systems (transmitters, receivers)
• 1/4 in:
  • To standalone recorders
  • From instruments (guitars, keyboards)
• XLR:
  • To standalone recorders
  • From performance microphones

7. Remembering general tips

1. Avoid hard, flat surfaces ('Look up, look down, and all around')
   • Use household blankets or acoustic foam
2. Put mic (and person) in comfortable position
3. Be within one hand-length or two fist-lengths
4. Set input volume/gain for around -12 to -10 dB
   • Recite alphabet or describe something in usual voice
5. Record 3-5 sec of silence at beginning and end
6. Use accessories if needed (windshield, pop filter)

Part 2: Audacity

1. Setting up Audacity

• Open-source (free) software
• First release in 2000; frequent updates
• Download & install for Windows, macOS, or Linux
• Download & install FFmpeg plugin for more file-types (M4A, WMA)

2. Examining the interface

1. Menu bar: File, Effect, View menu
2. Toolbars: Playback & recording, special tools, view
3. Audio Setup: Devices & other setting
4. Volume meters/levels: Input & output
5. Timeline & canvas: Tracks, track controls, clips
6. Tracks:
   • Delete [x]
   • Settings [...]
   • Mute vs Solo: Solo mutes all other tracks that don't have Solo enabled
   • Gain [-/+]: Increase/decrease to volume (dB)
   • Pan [L/R]: Shift audio left/right
7. Info panel: Project rate, timestamps, playback speed

3. Opening projects & importing tracks

• Opening Audacity project (AUP3) files
  • File -> Open ...
• Importing audio files (MP3, WAV, M4A*)
  • File -> Import … -> Audio
    • Default: Imported files have separate tracks (lanes)

4. Converting mono tracks to stereo tracks

• Track-level settings [...] -> Split Stereo Track or Split Stereo to Mono
  • Results in two separate tracks; delete as needed
• (Menu bar) Tracks -> Mix ->Mix Stereo Down to Mono

5. Understanding playback controls

• Three vertical lines
  • Marker: Black line (always shown, sometimes not obvious)
    • Click body of track/clip or click Skip To button
  • Skimmer: White line (only if stopped)
    • Move cursor along timeline
  • Playhead: Green triangle, black line (only if playing/paused)
    • Click timeline or click Play button
• Main functions
  • Pause [P]: Freezes/unfreezes; maintains positions of playhead
  • Play [Spacebar]: Plays (if possible) from marker position
  • Stop [Spacebar while playing]: Removes playhead; enables selection & editing
  • Loop [L]: Repeats playback of any highlighted clip
• View functions
  • Zoom In [Ctrl/Cmd + scroll-wheel up]
  • Zoom Out [Ctrl/Cmd + scroll-wheel down]
  • Fit Selection to (screen) width
  • Fit Project to (screen) width

6. Selecting & moving clips

• Selecting clip(s)
  • Single-click head (title section)
  • Double-click body (waveform section)
  • Single-click track title (track-level controls)
• Moving clips
  • Drag (by head) & drop (space needed)
    • Clip stays in original position while moving until desired location has enough space
  • Cut & paste
    • Cut: Select clip, then right-click -> Cut or press Ctrl/Cmd + X
    • Paste: Set marker, then right-click -> Paste or press Ctrl/Cmd + V

7. Removing clip portions

• Highlight & delete
• Drag edge
  • Point cursor to upper-half of body (above top waveform)
• Split & delete
  • Set maker, then right-click -> Split Clip or press Ctrl/Cmd + I

8. Monitoring volume

• Watch as well as listen
  • Measure vs interpretation; safety considerations
• Ideal/recommended volume (peak or majority values):
  • Primary audio: -12 to -6 dB
  • Secondary audio: -24 dB to -18 dB

9. Adjusting volume

• Set peak to specified (dB) value: Normalize
  1. Select clip
  2. (Menu bar) Effect -> Volume & Compression -> Normalize ...
  3. (Window) Set Normalize peak amplitude to [-12 to -1] dB
  4. Click Apply
• Minimize background noise: Noise Reduction
  1. Select portion for sampling
  2. (Menu bar) Effect -> Noise Removal and Repair -> Noise Reduction
  3. (Window) Click Get Noise Profile
  4. Select clip/portion for application
  5. (Menu bar) Effect -> Noise Removal and Repair -> Noise Reduction
  6. Input values and/or preview as needed
  7. Click OK
• Fade in/out audio: Fade In / Fade Out
  1. Select portion
  2. (Menu bar): Effect -> Fading -> Fade In or Fade Out
• Manually set inflection points: Envelope tool

10. Recording to Audacity

1. (Toolbar) Audio Setup -> Rescan Audio Devices
2. Audio Setup -> Recording Device -> [Input device]
3. Audio Setup -> Recording Channels -> 1 (Mono) Recording Channel (recommended)
4. (Record Meter) (Mic icon) -> Enable Silent Monitoring
5. Adjust input position and/or Recording Level icon
6. Click Record (circle) button or press R (for separate track, press Shift + R)
7. Click Pause (two rectangles) button to pause/resume or Stop (square) button to stop

11. Saving / exporting work

• Saving Audacity projects (AUP3)
  • (Menu bar) File -> Save Project -> Save Project or Save Project As ...
• Exporting standalone audio
  • (Menu bar) File -> Export Audio ...
    • Set Format dropdown to WAV or MP3
    • Set Export Range radio button to Export Project

Attributions

DELOSound. (2024, November 19). Suspense pulse tense music [Music score]. Pixabay. https://pixabay.com/music/upbeat-suspense-pulse-tense-music-266060/

Rode. (2015, July 15). What are a microphone’s polar patterns? Rode. https://rode.com/en/about/news-info/what-are-a-microphones-polar-patterns

Rode. (2022, August 2). What is a condenser microphone and when to use one. Rode. https://rode.com/en/about/news-info/what-is-a-condenser-microphone-and-when-to-use-one

Resources

• Creative Commons
• Copyright-clear/copyright-free audio
  • Freesound
  • Pixabay