1. Audio Video Production
Audio Basics
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

2. Sound Sound has two basic characteristics:
Loudness - measured in decibels
Frequency - measured in Hertz
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

3. Loudness dBSPL (sound pressure loudness) Measure of acoustic power
Jet
Rock Concert/ Gunshot
Jackhammer
85-90
City Street/ Restaurant
70-75
Quiet Conversation
60-80
Office Environment 45
Whisper 30
“Silent” studio 20
dBSPL (sound pressure loudness)
Measure of acoustic power
Sounds we can hear with our ears
135 dB is considered “threshold of pain”
Ears ring
Point at which hearing damage can occur
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

4. Loudness dBm Unit of electrical power Measured with VU meters
Digital VU meter
Analog VU meter
In live production, “0” is considered the maximum desirable sound level
0 is also called “Unity”
In post-production, the audio levels are between -12 and -6 dB.
“0” should NOT to be reached
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

5. Frequency Basic pitch of sound (how high/low it is)
Audible (hearing) range: 20Hz - 20,000Hz
20Hz - extremely low pitch, rumble
20,000Hz - extremely high pitch, higher than highest note of a violin
Common hearing range: 50Hz - 15,000Hz
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

6. Acoustics
Most sound booths incorporate different types of soundproofing materials
Hard walls; tile floors will allow too much reverberation
Reverb - sound remaining after the original sound stops
Too much soundproofing causes a dead, lifeless sound
Ideal room for recording and listening has free-standing, sound-absorbing items (furniture, rugs)
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

7. Types of mics Dynamic microphone
Uses a small coil that moves within a magnetic field when activated by sound
Pros:
Rugged and durable
Can withstand weather and rough handling
Great for ENG (electronic news gathering)
Low Cost
No power necessary
Cons:
Larger and heavier
Not the best choice for quality audio
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

8. Types of mics Condenser microphone
Has a plate that moves against another plate to produce a signal
Pros:
More sensitive
Better quality
Can be small
Cons:
Fragile and sensitive to shock and temperatures
Needs power
Battery
Phantom power supplied by camera or audio mixer
Expensive
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

9. Types of mics Ribbon microphone
Uses a small ribbon (rather than coil) moving in a magnetic field
Similar to condenser mics in pickup quality and sensitivity
Produce warm, rich sound
Very sensitive to rough handling and moving air
Rarely used outside an audio booth
LuckyLouie. RCA 44 Ribbon Microphone. 4 November <
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

10. How microphones “hear”
Microphone Pickup Patterns
Omnidirectional
Picks up sound in all directions
Unidirectional (cardioid)
Focused hearing in one direction
Cardioid - “heart-shaped” pickup pattern
Hypercardioid - narrow pickup pattern with a “long reach” (for distances)
Omnidirectional
Cardiod
Unidirectional
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

11. How mics are used Handheld mic Lavalier (lapel) mic Boom (shotgun) mic
Desktop mic
Headset mic
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

12. Handheld Microphone Held by the talent
Allows for talent to control mic’s location
Reporter can easily move it closer to interview
Singer can control intimacy of the sound by holding it closer
Field reporters - need dynamic handheld (rugged, durable)
Singers - need condenser handheld (better sound quality)
Disadvantages
Can be distracting (takes up visual space)
Talent’s hands are not free
Quality of sound depends on proper placement by talent
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

13. Lavalier Microphone Small, rugged, omnidirectional
Usually clipped to shirts six to
eight inches below talent’s chin
Advantages
Talent can move freely
Mic never moves
Sound is consistent
Disadvantages
Each on-camera subject requires mic
Requires proper setup and placement
Clothing may rub mic or muffle sound
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

14. Lavalier Microphone “Dressing” lapel mics (hiding wires)
Under clothing
Have talent run microphone under the shirt
Clip mic to tie, lapel, collar or button flap
Careful of material rubbing mic or obstructing sound
Outside clothing
Run mic up the back of talent (outside clothing) and over the talent’s shoulder near the collar (under collar if possible)
Clip mic to lapel, collar, or button flap
Use gaffers tape (on talent’s back) to keep the mic cable from moving
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

15. Boom Microphone
Unidirectional mics intended to pick up sound without being seen on camera
“Shotgun” microphone mounted to the end of a telescoping boom pole
Pole has shock-mount to absorb all movement
Can be held above talent or at low angle below
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

16. Desktop Microphone Microphone mounted on a small stand
Used for fixed positions
Often seen in:
Game shows
Speeches
Board rooms
Churches
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

17. Headset Microphone
Gives talent the freedom of movement while keeping the mic close to the mouth
Sometimes includes an earphone for talkback
Important for loud arenas and stadiums
Used by sportscasters, musicians/performers and public speakers
Small, wireless headsets with no earphone are sometimes called “countryman” mics
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

18. Wireless Microphones
Involves a microphone with a transmitter and a wireless receiver
Can come in any style
Lav, headset, hand
Allows complete freedom of movement without wires
Transmits through frequency bands
UHF
Least interference
More expensive
VHF
Cheaper
Most interference
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.

19. Windscreens
Designed to let normal sound frequencies through and filter out wind noise
Made of acoustic foam rubber
Windsock
Used for shotgun mics
Ragged cloth that is pulled over the windscreen
Copyright © Texas Education Agency, All rights reserved. Images and other multimedia content used with permission.