Sound Recording Techniques in Film

Sound Capture

• The sound mixer is the most senior role on the sound team, responsible for balancing the audio.
• The boom operator captures sound using a boom microphone and works closely with the mixer and set staff.
• Sound assistants provide support for the sound department, including equipment maintenance, battery checks, and data management.
• Sound trainees assist with general tasks and gain hands-on experience.

Location Sound Recording

• The goal is to capture high-quality audio.
• Poor location scouting can lead to sound problems from sources like planes, generators, hallways, and animals.
• Location sound is captured while the camera is rolling.
• Production sound encompasses all audio recorded on set.

Types of Production Sound

• Sync audio is recorded simultaneously with the camera and includes:
  • Dialogue: actors’ lines captured from a single source like a boom mic
• Wild audio is recorded without the camera rolling and includes:
  • Wild tracks/lines: dialogue recorded separately from the camera
  • Ambience/background loops: recordings of ambient sounds, including:
    • Roomtone: sound of silence in a room
    • Natural sound: sound of silence in an outdoor location
    • Wild sound effects: specific sounds from a location used during filming

Audio Essentials

• Sound in film is relative, not absolute, and exists only in time.
• Analog audio is continuous, while digital audio uses computer software.
• The decibel (dB) is the unit of measurement for all audio.

Human Hearing

• We hear sounds between 20Hz and 20,000Hz.
• The Fletcher Munson curve demonstrates that we don't hear all frequencies equally, and sensitivity varies.
• Loudness is not the same as volume, and perception is influenced by frequency and duration.
• The phon is a unit of perceived loudness.

Sound in Film Production

• Multiple roles contribute to film sound including:
  • On-set sound recording
  • Sound editing in offline editing
  • ADR (Automated Dialogue Replacement)
  • Foley
  • Composer
  • Music recordists/editors
• AI tools are increasingly used for sound creation and manipulation.

Importance of Sound in Film

• Sound contributes significantly to conveying emotion and directorial intention to the audience.

Digital Audio

• Digital audio is the representation of sound in a digital format using discrete measurements.

Sample Rates and Bit Depth

• Sample rate determines how many measurements are taken per second, affecting the highest frequencies recorded.
• Bit depth defines the quality of each sample, affecting the dynamic range.

Converting Sound

• All sounds begin as pressure changes.

Polar Patterns

• Condenser microphones require a boost.
• Lavalier mics are omnidirectional.

Explore the essentials of sound recording in film production through this quiz. Understand the key roles in the sound department, including the mixer, boom operator, and support staff. Test your knowledge on capturing high-quality location sound and the different types of production audio used in cinema.