• Characteristics of sound
• Frequency
• Amplitude
• Problems with Camcorder Mikes
• When to Use External Mikes
• Different Plugs Used
• Microphone Types
  • Characteristics
  • Pick Up Patterns
  • Advantages of each type
  • When to use each type
• Recording Audio Indoors & Outdoors ---Strategies & Techniques
• Mike placement
• Troubleshooting if sound is bad
• Field Audio Kit
• Auto gain Control
• ESSENTIAL TIPS
• Audio Editing/Soundscapes (More on Editing Later)

REMEMBER SOUND BOUNCES OFF SURFACES!

Frequencyof Sound: number of cycles of compression and expansion per second (Hertz or HZ) This corresponds to the PITCH of the sound.

Amplitude (loudness) and waveshape (timbre, or tone color) are two other characteristics of sound.

• No manual level control
• No ability to record multiple tracks with good isolation
• “Stereo” mikes pointing in the wrong direction.
• Not able to isolate specific sounds

Think of what happens to audio if you are recording a speaker in a lecture hall. You can zoom in to get a closer look but not a closer sound. Camera mike picks up every sound made when you touch the camera body. And all sound which is recorded closer to the mike is louder than what is away (even your breath will sound loud). Sometimes (in a rock concert) the mike might be too sensitive for the loud sound. And if you are outdoors the wind hitting the camera mike will cause distortion. 

Also, remember that sound bounces off surfaces...which means that the further you are freom the subject, the more likely you are to pick up all the reverberations, the bouncing sound waves, from your surroundings.

So you have to use an external mike.

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(1)  Dynamic vs. Condenser 
(2) Pick Up Pattern
(3) Type of Mike --- by Placement

Dynamic Microphones

What are they: 
"The dynamic microphone has a fixed magnet, a diaphragm that moves when sound hits it, and a coil attached to the diaphragm. When the diaphragm moves, the coil moves, making changes in the magnetic field. These changes generate voltage through the microphone cable to the recorder, amplifier or speakers."
Source: Robert Nulph Sound Track http://www.videomaker.com/scripts/article.cfm?id=7702

• More rugged
• Can tolerate wide temperature ranges and humidity 
• Handle very loud sounds without distortion
• Warmer sound
• Less vulnerable to wind
• Requires no outside power

• Crisper sounding
• More sensitive to faint signals
• Easily overloaded by loud signals
• More susceptible to wind noises (needs wind screen)
• Require power for their circuitry (often a AA battery)
• Better frequency response

FOLLOW THIS LINK FOR ILLUSTRATIONS OF PICK UP PATTERNS

• Omnidirectional

• Picks up sounds coming from all directions
• useful for background noise 
• does not allow isolation of sounds

• Directional (cardiod) 

• most sensitive to sounds coming from the front, less sensitive to sounds from sides, least sensitive to sounds from behind.
• As sound source moves from the pick up area, high frequencies are first to be lost.
• These mikes do not Zoom into sound (they do not "magnify" like a zoom lens.) Instead, they isolate by excluding competing background sound, thus allowing recording of better sound at a distance from mike.
• approxinmately 60 degree angle of reception.

• Hypercardioid( (mini-shotgun)

• Narrow angle of sensitivity
• Less sensitive to sounds coming from behind or sides.
• Excellent at isolating sound, but can be a problem if sound source falls off-axis, outside the angle of sensitivity.
• aim at chest

•  Supercardiod (Long shotguns) 

• most extreme, must be pointed at mouth of speaker/chest
• Must always be monitored because it is easy to go off-axis.
• Avoid handling the tube, as this is what makes it hyperdirectional.
• Extremely insensitive to sounds outside the sensitivity angle.

• Lavaliers 

• Placement: Tie Clip
• Omni Directional
• Good for isolating speaker's voice (esp. in interviews)
• Isolates voice because it is close to source of sound (not because it is directional)
• Can pick up rustle of clothes and movement
• Wireless models use radio transmitters. Can be convenient, but can also pick up interference from radio transmissions such as cell phones.

• PZMs

• Placement: table-top
• Omni directional (up away from table).
• great for picking up localized conversations.
• pick up  noise on table or resting surface.
• Must remain near microphone for best sound, limits mobility of speaker.

• Shotgun Mikes (directional)

• Placement: Aimed at speaker's chest for best/most robust sound
• Placement: On boom pole
• See Above for characteristics/advantages/disadvantages.

• Microphones

• battery
• matching transformer if not balanced
• wind screen

• Cables

• XLR cable (grounded)
• XLR to Mini Adaptor so you can plug mike into camera audio jack
• extension cable

• Boom Pole (for shotguns)

• Pole
• Shock Mount (never hand hold mikes)

• HEADPHONES

• AN ABSOLUTE NECESSITY ---The only way to really know if you are recording sound and what sound you are recording!!!!!!
• Use the big ones that cover your ear (not the small ones that fit in your ear) so you can isolate outside sounds more effectively.

• Gaffer tape to use as necessary.

• Always use headphones to monitor your sound recording. ALWAYS.

• Always be aware of all noise (air conditioning, heater, refridgerator, flourescent lights, computer screens...everything makes noise!!!)

• Be aware of the reflective potential of your space. If you are in a hard wood floor apartment, sound will bounce differently than in a carpeted one. Hang blankets on your walls to muffle sound bouncing off walls. 

• Always aim your mike away from potential noise sources (mentioned above, this includes a wall that reflects sound). 

• Always record at least 1 minute of room tone for each location you shoot in. This will be used later in editing to hide cuts.

• Always record sounds independently of each other (or as independent as possible). For example: if you want to film a scene where someone is listening to a song on the radio, then record the scene without the music (with action, dialogue, etc) then record the THE MUSIC. You would then MIX music with the dialogue AND room tone. If you attempt to record the scene by recording the music as you film the action, each cut in the action will create a hideous cut in the MUSIC!!! Same goes for any other special sound effect you might have in your scene. (including ambient sound)

• REMEMBER, you can always ADD more sound on different tracks but you cannot take away sounds from a single track!!

• Think of yourself as creating a SOUNDSCAPE that is always as important as your visual imagery.

• Distance is Everything. The Closer you place the mike to the sound source, the better the sound you will get.

• Try to match your voice recording, levels, tones, intimacy, etc, with the composition of the shot. Ex:A close-up monologue does not need sound recorded at a far distance, but a rich soft tone recorded at an intimate distance.