Audio Basics Session 03

OVERVIEW Announcements Audio basics Sound dimensions Digital aspects of audio production Sound pickup principle Microphones Cables and connectors Definitions Recording activity Preview next session

ANNOUNCEMENTS 6pm time for rest of semester Save any work to Documents folder Not desktop (it will be deleted) Closing down the Macs –At end of class; quit all applications (not just close window) For example Safari menu > Quit –Apple icon in upper left corner > Shut down (but do Not log out) Added links page to –Storyboard and scriptwriting –More as we progress through course

AUDIO BASICS Audible vibrations or oscillations of air Sound –Has purpose –Is organized –Is wanted Noise –Essentially random –Typically unwanted Same audible vibration could be sound today and noise tomorrow

AUDIO BASICS Clean, clear, consistent, coherent All connected to reducing noise, acquiring sound Literal sounds –Convey a specific literal meaning –Help tell the story by connecting to on-screen visuals Even if speaker leaves scene but you still hear voice its connected –For example, teacher talking and student responding Non-literal sounds –Not intended to convey literal meaning –Are deliberately disconnected from on-screen visuals –For example, most musical accompaniment

INFORMATION FUNCTION Direct address –Speaker speaks directly to viewer –Talking head –Primarily used to provide information Dialogue –Two or more people –Primarily used to communicate theme via question and answer –Interview skills required Narration –Supplies additional information/material –Describes screen event or bridges gap for continuity –Often off-screen voice-over –Typically spoken word

SOUND DIMENSIONS Rhythm –Pace –Relative to visuals Figure/ground –Choosing important sounds to be figure while relegating other sounds to background –Reporter’s voice more predominant than natural, ambient sound in background Sound perspective –Matching close-up shots/visuals with “close” sounds –Matching long shots/visuals with sounds that seem from farther away Sound continuity –Sound maintains its intended volume and quality over a series of edits Listener perception effected by: –Microphone changes from scene to scene –Expectation given the overall aesthetic experience –For example, classroom scenes typical signal to us certain expectations –For example, Wild Kratts boat sound

SOUND DIMENSIONS Puzzle #1 –Nature scene –A visual figure/ground task

SOUND DIMENSIONS Puzzle #2 Mathematics word problem Auditory processing problem –Listener perception and expectation

DIGITAL ASPECTS Record to digital formats directly –Via camera’s microphone –Via microphone to computer –Via microphone to digital audio tape –Via microphone to hard disk recorder Music –MIDI –Live –CD Monitor –Speakers make a big difference –Listening to something on your mobile device is not the same experience as a full stereo with subwoofers –Monitor with headphones while recording (on camera) Edit –Software has many features –Editing, splitting, copying, mixing, effects –Clean, clear, consistent, coherent still applies on recording Dissemination –Export to file for computer –DVD –Podcast –Web page –App

SOUND PICKUP PRINCIPLE Microphones transduce sound waves into electrical energy Microphones transform sound into a signal Signal made audible through speakers/monitors Computers transform into digital

MICROPHONES Different mics for different purposes –Find out if your school or organization owns any mics –Find out what kind, what type of connections at end of cable they have Good audio means choose the right mic for the sound pickup task Classified by –How well they hear –How they are made –How they are typically used

HOW WELL THEY HEAR Pickup pattern –Omnidirectional Hears equally well from all directions Think of mic at center of a sphere Sphere represents the pickup pattern –Unidirectional Designed to hear from one direction-the front Think of mic at top of heart shape Heart shape represents the pickup pattern Sometimes called cardioid

HOW WELL THEY ARE MADE Dynamic –Uses small coil that moves within magnetic field when activated by sound –Rugged –Works well with close sounds and loud sounds Snare drum –Often have pop filter for close talking phonemes Go to instructables.com search for microphone pop filter Condenser –Uses a moveable plate, a diaphragm, that oscillates against a fixed plate to produce signal –Less rugged, more sensitive to temperature, physical shock –Produce higher quality sounds –Works well with indoor sound pickup of crucial sound –Need a power supply Some have battery Others through console Ribbon –Uses a tiny ribbon that moves in a magnetic field –Highly sensitive –Works well for musical recording in highly controlled environments

HOW TYPICALLY USED Lavalier Hand Boom Desk and stand Headset Wireless

LAVALIER Lav for short Sometimes called lapel Small, rugged, omnidirectional Voice pickup Distance from mic to voice typically does not change Good for instructors, talking head, dialog/interview If noisy environment surrounding, ambient noise can be picked up Attached to clothing means rubbing of clothes if talent moves Concealed partially under clothes, in pockets, talent must wear appropriate garments Possibly muffled by clothing

HAND Handled by talent Used where talent must exercise some control over sound pickup –Under normal conditions speak across mic rather than into it –Reporters, singers, hosts Outdoors Check action radius of the mic cable –Will cable get caught on objects in environment

BOOM Mic connected to boom Boom out of picture Suspended by boom Often hypercardiod or supercardiod (shotgun) mics used because Mic is usually farther away from source than lavalier or hand Check the reach of boom before taping Check that cable and mic are fastened Monitor boom mic with headphones during taping Watch for shadows that boom may cast You can be the boom and just point a shotgun mic at a person

DESK & STAND Mounted on tabletop Used for panel shows, public hearings, speeches, news conferences One mic per person typically; can share for panels Multiple mic interference if positioned too closely –Place individual mics three times as far apart as any mic is from its user Tape mics to table; tell guests not to touch

HEADSET Sportscasters, singers, live events from field Combined with earphones Talent can hear the program sound including his/her voice in one ear and instructions from producer/director in other Hands free

WIRELESS Also called radio mics From transmitter to receiver Receiver connected to mixer, audio console, possibly camera

CABLES & CONNECTORS ¼” phone jack/plug mono XLR Connector 1/8”or 3.5 mm mini-plug stereo

CABLES & CONNECTORS RCA phono plug MIDI

ADAPTERS of ALL KINDS 1/8” mini-plug to ¼’” phone plug 1/8” mini-plug to XLR

LINE LEVEL Line level refers to strength of audio signal Most mics are not line level Mic level is usually lower than line level –Results in low levels on recording Most computer sound cards want line level Most mics need pre-amplification using a preamp or mixer to increase pickup –Mic to preamp to computer –Avoid boosting gain too much –Signal to noise ratio –Gain is Preamps range in cost

DEFINITIONS Amplification –strengthening of an audio signal for an increase in loudness Attenuation –signal loss, a lowering of level Gain –How much an electronic circuit amplifies a signal, measured in decibels Line level –type of level (strength) of electrical signal used in professional audio equipment Professional gear is +4 dBu (1.23 volts) and consumer line level is -10 dBV (0.316 volts) Mic level –type of level (strength) of electrical signal used in professional audio equipment, generated by the microphone; about 60 dB lower than line level

PROCEDURES Plug in your cables/connections Turn on preamp if necessary –Some are USB Position mics if lavalier or on stand – Proximity is important –Hold close to mouth –Squat down to interview child so visually on level plane Prepare to monitor on recording device (camera, mixer, computer) with headphones Test mic prior to taping –Get level Do not blow, whistle, tap, whack Generally just talk, count Remember fresh batteries if necessary

SET UP TODAY 6 mics –Shure SM57 Dynamic, unidirectional, cardiod, instrument mic including vocals –Shure SM48 Dynamic, unidirectional, cardiod, voice and vocal mic –AudioTechnica shotgun mic Dynamic, unidirectional Uses a battery –StudioProjects Condenser Requires phantom power from preamp –2 lavalier mics “Prosumer” mixer Handheld mics using XLR into mixer –Wireless going 3.5mm (1/8”) adapter into ¼” phone plug on mixer Mixer using XLR output adapted to 3.5mm mini-plug (1/8”) on iMac On the Mac –Sound control panel/system preferences set to line in and input level adjusted In GarageBand –In Preferences> Audio/MIDI> Input set to System Setting

RECORDING ACTIVITY Record voices Volunteers to read passage Run through most of the mics –Once line into computer –Once line into mixer, then into computer Selection –Green Eggs and Ham by Dr. Seuss Read just your “start with” one time, then your lines of the text then stop Try to read like you are being recorded, articulate, lets hear every syllable, use your own rhythm and phrasing We will listen back for changes in recording level and discuss

NEXT SESSION GarageBand intro