ch06_ch06_presentation

Chapter Overview

• This chapter covers the essential aspects of audio for television production, including types of sound, microphone functions, and operational guidelines.

Objectives

• Explain the function of audio for television productions

• Identify the most common microphone types

• Importance of pick-up pattern classification

• Recall VU meter readings for digital audio systems

Functions of Audio

• Audio is critical in film and television for conveying messages.

• Types of Sound:

  • Voice Track:

    • On-camera dialogue

    • Off-camera narration (Voiceover - VO)

  • Music and Sound Effects:

    • Sets the mood and enhances action/emotion

    • Sources for sound effects include:

      • Created by production team

      • Purchased or downloaded

  • Environmental Sounds:

    • Natural sounds highlight the story, often recorded with B-roll.

    • Background Sound: Ambient sounds establishing setting without overpowering the primary audio.

Environmental Sound Manipulation

• News Programming:

  • Maintain natural sounds, modify only to ensure clarity of reporter's voice.

• Non-news Programming:

  • More extensive manipulation is acceptable.

Room Tone

• Unique to each location; vital to record room tone for edits.

• Helps in eliminating unwanted sounds during editing.

Sound Frequencies

• Low Frequency Sounds:

  • Instruments like bass guitar, tuba

  • Bass vocalists

• Mid-Range Frequencies:

  • Instruments like trumpet and clarinet

  • Alto and tenor voices

  • Human speech

• High Frequency Sounds:

  • Instruments like flute and piccolo

  • Soprano vocalists

Microphone Types

• Dynamic Microphone:

  • Rugged design, suited for speech, mid-range sound.

• Condenser Microphone:

  • Requires external power, broader frequency range.

• Ribbon Microphone:

  • High quality, high cost, fragile, used in studios.

• Non-professional Microphones:

  • Found in low-end camcorders with limited pick-up range.

• Specialized Microphones:

  • Boundary Mic: Captures sound from an entire area.

  • Parabolic Reflector Mic: Used for capturing distant sounds, e.g., sports events.

Pick-Up Patterns

• Omnidirectional Microphone: Picks up sound equally from all directions.

• Directional Microphones (Cardiod, Supercardioid, etc.):

  • Heart-shaped patterns focusing on sound from one direction.

Feedback and Recorders

• Feedback: High-pitched noise from feedback loops, potential speaker damage.

• Portable Audio Recorder:

  • Produces high-quality recordings, needs sync with video.

Mic Positioning Techniques

• Hand-held Mic: Hold at sternum level for stability.

• Boom Mic: Keep it close to talent without entering the shot.

• Lapel Mic: Very small, worn by talent, also called lavaliere mic.

Cable Guidelines

• Keep mic cables and AC cables separate, cross at 90-degree angles if necessary.

Impedance Signals

• High Impedance (HiZ): Economical, limited to short cable runs.

• Low Impedance (LoZ): Prized for quality and can support long runs, used in professional gear.

Sound Levels and Mixers

• Levels to be aware of: Mic level, Line level, Power level; they cannot be combined.

• Mixers help combine audio signals:

  • Mic Mixer: Combines mic signals only.

  • Audio Mixer: Combines different sound sources.

Volume Unit Meter (VU Meter)

• VU Readings:

  • For analog: +3 to -3 dB

  • For digital: around -20 dB.

Headphone Guidelines

• Use headphones covering the ear to accurately monitor audio.

• Avoid consumer-grade headphones as they don’t block outside noise.

Automatic Gain Control (AGC)

• Controls audio levels with a slight delay; not suited for analog recording due to tape hiss.

Career Overview

• The Audio Engineering Society is the only professional body focusing exclusively on audio technology.