Location Sound Basics

This overview summarizes the most important points about on "location sound recording" or "field recording", split into pre-production, production and postproduction.

1. Introduction

Central questions

  • How do I design the soundtrack of a short video, which on the one hand shows a "real" application situation, on the other hand clarifies a concept?
  • Which audiovisual styles do I orientate myself on (feature film / documentary / reality TV / advertising...)?
  • How can I use sound to support the narrative?
  • How can I use the sound to have more possibilities on the visual side (and vice versa)?

Also read: Randy Thom, Designing a Movie for Sound http://filmsound.org/articles/designing_for_sound.htm

Some functions of audiovisual narration: 

  • Creating credibility and realism through sound 
  • Rhythmization / vectorization of the image
  • Diegese: Is a sound part of the depicted world?
  • Narrative perspective, camera perspective, sound perspective
  • Sound semiotics: sounds and music as signs (e.g. ticking = time), "potentials of meaning".
  • Sound semantics: material / movement / space, setting, scenography / symbols / keysounds ...


2. Pre-production

2.1. Audiovisual storyboarding, spotting

  • Scripting
  • Storyboarding (audiovisual)
  • Spotting sounds: determine sounds for individual settings according to script / storyboard

2.2. Planning the recordings 

  • Location: Access, Soundscape
  • Foley: Suitable room (quiet, "dry"...)
  • Effects / Sound Design Raw Material
  • Set Dialog
  • Voice Overs / Dialogue Replacement


2.3 Microphone: technology and application

Rule Nr. 1: What you hear is NOT what you get!

  • Microphone is not a camera lens

  • Microphone types (dynamic, condenser, ...)

    • Professional connectors: XLR. Advantages: Grounding, shielding, stability. If available, always prefer!

    • Polar patterns: omnidirectional, cardioid, hypercardioid, shotgun, pressure zone mic.

      • Examples: Sennheiser me64 & me67

    • Stereovariants: A-B, Eight, XY 

      • Example: Rode NT 4

    • Mono (dialog, effects..) 

    • Stereo (Atmos, certain dialog settings with static / perspective miking)

    • Sound change through distance & alignment. 

    • Phantom power 48v with condenser microphones: via circuit or batteries.


Choosing a microphone for dialogues

(priority: sound quality, naturalness, effort, reliability): 

  1. Hypercardioid or shotgun with boom, over head
  2. Hypercardioid or shotgun with boom, under head
  3. Cardioid, hypercardioid, boundary zone or shotgun combined (depending on ambient noise and proximity)
  4. Lavalier in a set (wired)
  5. Lavalier on the protagonist (wired)
  6. Wireless lavalier


Combine multiple microphones to be able to correct mistakes in post-production.

In addition to the recording microphone, it is worth recording a more distant microphone or a room microphone (stereoatmo).

Lavaliers are the first choice for certain settings (e.g. conversation recording, discrete environment).

Booming

  • Preserve the natural power of a performance 

  • Useful for SFX recording ("ride along", or remote sources)

  • Needs an "operator". 

  • Use Shockmount (damped microphone mount / "spider")

  • Mic selection: Narrower polar pattern = more sensitive for motion tracking

  • Boom orientation: ideal from the top front towards the mouth. At most two close persons can be recorded in this way

Lavaliers (von Louise de La Vallière)

  • Beneficial when recording conversations. Disadvantage: sometimes they have to be hidden, and they don't sound as good as a good boom mic. If a lav is mounted incorrectly, clothing noises can completely destroy the recording. The closer the less "natural" spatial sound characteristic -> can be counteracted by simultaneous recording with room microphone.

  • Polar pattern usually omni, alignment not so important. 

  • Consider head movements: The more freedom needed, the further away from the mouth. Sometimes two lavs are mounted 

  • Ensure cable relief (e.g. by attaching the cable to the clothes)!

  • Adhesive tape / gaffer tape helps to mount the lav so that it does not rub against clothes (Attention: glue residues!).

  • Lavs as static mic also makes sense, but only if source is close enough.


3. Production: on Location

Rule Nr. 2: Trash In, Trash Out (and 2b: You Can't Fix it in Post)

3.1. Recording

  • One minute of silence! Atmotrack, room-tone
  • Always monitoring with headphones! Whenever possible, a separate person should monitor the recording!
  • Do not use "in camera" mic! (unless it is intentional aesthetics, or a sync guide track is needed)
  • Video standard: WAV, 48Khz / 24 Bit -> minimum quality
  • Single or double system: Normally the camera-internal recorder is sufficient if the microphone is used correctly. If an additionally external recorder is used ("double system") -> SLATE & shotlist & logging.
  • An external recorder can also beused as a backup track or for the ambient mix, or if several sound tracks are necessary.
  • Sound check before the recording!
  • Adjust level: Only if absolutely necessary, never during a sound event
  • Only use automatic gain regulation / limiting in an emergency

Room & Ambient Sounds

  • Carefully listen for reflections and noises. Optimise mic position accordingly
  • In closed rooms rather cardioids, outdoors rather shotguns, with additional Atmo Track
  • Always record "a bit too much" material (-> "handles", flexibility in cutting)