Sound II:
Microphones and Techniques
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1. Get mic close - for quality sound get microphone as close to sound source as possible within the context of the the goals and style of the production.
- hand held for news/POS - news, sports: mic is seen
- shotgun on fishpole - news or narrative: mic is not seen - lav (wired or wireless)
: may or may not be seen (be careful)
* Does the production crew need to be mobile and responding to changing situations?
- handheld (wired or wireless) or shotgun on fishpole
* Decide if you want the mic to be visible or not.
* Do you want the sound to seem 'far away?' If so, move the mic away.
2. Camera mic? - use the camera mic only as a last resort - picks up sounds
near the camera, usually not the sounds you want
* Quality of sound degrades exponentially as mic moves away from subject
* Chance of capturing unwanted sounds increases exponentially as mic moves away
from subject 3. Wired or wireless - in general, shielded cable is
less prone to interference than wireless mics.
* if convenient and appropriate, use wired mics
* wireless allow talent to move freely
4. Cables - cables should never run parallel to each other or video
or power cables and should cross at 90o to avoid interference.
- take care of cables to keep them from degrading: small cuts or breaks might
allow signals to bleed in
* wrap gently and tie with velcro cable ties
5. Actively monitor audio - always wear headphones and view the
VU (volume unit) meter to check the sound at the recorder/camcorder.
* check the levels on the VU meter to determine that the levels are solid (regularly
peaks at around or just above 0dB [zero decibels])
* levels consistently too high leads to distortion (+6-+18 dB) In the
red, pinning
* levels too low leads to lots of tape noise and problems in editing
In the mud.
* check sound in headphones at camera to make sure you are getting the sound
you think you are6. Distorted or Low Audio CANNOT be fixed in post-production
* Low audio - if it is boosted in editing, ALL sound on tape, including hiss
and background noise are boosted also
* Distorted audio - if audio is recorded too loud on the original tape, it is
virtually impossible to remove the distortion in editing... in other words the
audio is useless.
7. Microphone placement
* Handheld - leave it to the pros or take the time to coach talent
- keep mic still - new talent is prone to hand waving - 8 inches to a
foot from the mouth (don't eat the mic but keep it close) - if talent isn't
comfortable, you hold it for them - frame shot to minimize reporter's
arm in the shot
- if possible, frame the shot tight and have the mic off-camera
* Lav mic - first, evaluate talent placement and potential for movement.
- Any movement of the mic may affect the sound quality (e.g., mouth pointed
away from mic, mic rubbing/scraping on clothing).
- place mic near mouth, 8-12 inches away on lapel, tie or collar. Too
close = rumbling, popping, distortion; Too far = tinny, thin, low volume, room
noise. - place in center of chest if talent movement is likely - place
toward direction talent is speaking if the direction they will speak will be
consistent
(e.g., lengthy Barbara Walters type interview, if Babs is to the right of the
interviewee, place mic on the interviewee's right lapel)
- coil cable gently in clip, but don't pinch it - hide cable under clothing,
jacket, tie, blouse - tactfully. Anyone who is used to being interviewed
will know how to do this. - be courteous and respectful when asking talent
to hide the cables (pro talent won't think twice, rookies may hesitate). You
don't want the cables showing... it looks tacky.
- in a windy situation, create a gaff-tape cradle for the microphone under the
collar to reduce wind noise
* Shotgun or boom mic
- mount to a fishpole or boom and get the mic near the talent
- plan/work with shooter to determine shot composition and keep mic just out
of frame
- point mic toward sound source - pay attention and adjust as talent, shots
change
- try to point either upward or downward.... pointing straight ahead
(parallel to the ground) will likely pick up unwanted sounds from behind the
talent
- avoid banging cable on the fishpole, it creates noise
8. Ambiance - always record at least 30 seconds (a minute is better) of ambiance
- room noise, exterior sound
* ambiance may be needed in editing to cover voice-overs or other sound problems
* ambiance is a form of nat sound (natural sound) that is used under edits to
keep the background sound consistent with no dropouts
* to gather ambiance: let camera run for a minute and mark it on the field
log
9. Environmental noises
* be aware of unwanted noises that might interfere with the sound you are trying
to capture
* often we don't notice them on location, but will in post- production
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- nearby construction is terrible (saws, hammers, etc...)
- motors running really show up on tape
- air conditioning, heating can cause serious problems
- high frequency sounds are especially problematic
- be very careful in areas with a lot of scientific instruments, mechanical
devices or other radio waves (transmitters, receivers) as they may interfere
with (bleed into) your signal
- deal with it at the time of the shoot to avoid headaches later: ask people
to stop, move the shoot, find a way to get rid of noise
- apriori location scout will help identify potential sound problems
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Communication Studies Audio Gear (as of Feb. 2002)
* Professional Grade (XLR connections)
* All cameras now equipped with Beachtec XLR adapters
* 3 Audio Technica shotgun mics w/XLR (incl. 25' cables)
* 3 fishpoles for use w/shotguns
* 3 Samson wireless lavaliere mics
* 4 Sony handheld mics (XLR outputs but mini-plug cables enable plugging into
"normal" audio inputs on camera)
* headphones for each camera
* Start with Beachtec adapters turned up full, then adjust accordingly
based on VU meter and sound through headphones
* If using one mic, set adapters to Mono * "Prosumer" Grade Audio
Gear (1/8" mini plugs)
* 3 AT shotguns
* 3 AT wireless mic sets
Final notes
1. Make mic choice and placement a conscious, informed decision.2. Be
aware of all of the factors which may impact your sound gathering.3. Poor
quality sound can be disastrous and impossible to fix in post-production (editing).
4. Gathering quality sound is harder than it seems, and often harder than getting
good video.
5. Monitor the sound visually (read the meters) and aurally (listen to the headphones).6.
It is strongly suggested that you dedicate at least one crew position to audio.
7. Prepare! Don't wait until you get on location to figure out how the
mics/audio connections work.