Sound in an environment Sound wave –Compression / rarefaction Frequency / Measured in hertz Amplitude / Measured in decibels (db-spl) –AM/FM, kHz / MHz (r.f.) Attack/sustain (internal dynamics)/decay -- sound envelope Acoustics / Psychoacoustics / binaural hearing Absorbed / Reflected Direct / Indirect (echo & reverberation)

Some issues with sound Dynamic range – lowest to loudest sound level range Equal loudness principle--depending on loudness we don’t hear low and high frequencies as well as we hear middle Masking--Hiding of some sounds by other sounds by other sounds when each is a different frequency and they are presented together. Loud over soft / lower-pitched over higher Acoustical phase--the time relationship between two or more sound waves at a given point in their cycles Timbre--a sound’s unique tone quality or tone color

Studio / Facility Sound Design Ergonomics – human element in designing room Sound Absorption and Reflection Diffusion--scattering of sound waves Diffraction--spreading or bending Resonance--vibration of an object at the same frequency as the original body’s frequency Lively or Dead Room Isolation

Sound Frequency Spectrum Bass –Low bass, 1st & 2nd octaves, Hz –Upper bass, 3rd& 4th octaves, Hz Midrange –5th, 6th & 7th octaves, ,048 Hz –Upper midrange: 8th octave, 2, ,096 Hz Treble –9th & 10th octaves, 4, ,384 Hz

Analog / Digital When the true curves and nuances of a sound wave are encoded onto the recording medium, like tape, you have an analog recording Digital recording samples the audio waves and encodes the information into binary code to represent the waveform.

Digital vs. Analog Recording Analog: frequency is the time component and amplitude is the level –(frequency, cycles per second) –(amplitude = loudness) Digital: sampling is the time component and quantization is the level. –(sampling, like 44.1 kHz) –(quantizing, like 8 bit word / 16 bit word)

Digital Recording Sampling: takes periodic samples (snapshots, voltages) of the analog signal and converts that information into digital data Sampling frequency: the rate at which the signal is sampled: 44.1 kHz, 48 kHz Think of film at 24 fps – each still frame is a ‘sample’ (snapshot) of information in 1/24 of a second

Digital Recording Quantization: how many ones and zeroes to represent each sample A quantity expressed as a binary number is called a digital word. 10 is a 2-bit word, 101 is a 3-bit, 1010 is a 4-bit etc. The greater the number of the quantizing level ( an 8 bit vs. 10, a 2 bit) the more accurate the representation of the analog signal.

Signal Processing ‘DSP’ (enhancement) Bass roll off Compression Limiter EQ (graphic, parametric) Reverb unit

Mics -- Review Sound Sound Frequency Spectrum –Bass, midrange, treble Frequency / Hertz Amplitude / decibels Acoustics Direct / indirect sound –Echo / reverberations

More issues with sound Sound envelop -- attack sustain decay –Attack, initial decay, sustain, release Velocity--speed of the sound wave (examples) –1,130 fps at sea level –11,700 fps in wood –18,000 fps in steel

Microphone Directional Patterns Omnidirectional / nondirectional Unidirectional / Directional/ cardioid –Super, hyper, ultra Bidirectional

Main polar patterns Omni / nondirectional Bi-directional / figure 8 Unidirectional / directional / cardioid

Cardioid range Cardioid Supercardioid Hypercardioid Shotgun mic is hyperdirectional Phase cancellation

Professional Mic types Moving coil/dynamic Ribbon Capacitor/condensor Transducer – changes energy from one form to another – in this case sound waves into an electrical current

More about mics and sound Close vs. distant miking –Cross-pair, mid-side as some distant miking approaches –Close mic speakers on camera / filmmaking wide shots must do ADR Wide response – range of frequencies the mic will pick up Flat response – accurately recreates frequencies Colored response – changes frequencies (lavaliere boosts high frequencies, for example

Close / distant miking All foreground audio is close-miked Background (walla, nat sound) audio is distant miked ADR compensates for long shots, actors re- record and new dialogue is processed and looped in Showing / not showing the mic

Common mic types lavaliere headset Handheld (stick) studio/boom mounted TV boom types / largest to smallest –Perambulator boom, giraffes, fishpole PZM (boundary mic) #

Miking applications Movie / TV show scene –Boom pole, ADR (how done) News anchor / reporter Talk show host Play by play announcer DJ / audio spot production Orchestra on a stage

Movie sound Ambience –Walla Foley –Foley stage, foley artists –Ben Burtt / Sound Design Score Layering Dolby Surround###