Sound Design and Technology

ROP Stagehand Technician

Functions of Sound in Theatre

MusicEffectsReinforcement

Music

Create aural atmosphere to put the audience in the proper mood for the play• Preshow, intermission, postshow• Includes constructed sound (and sound effects

created by editing, manipulating, or changing previously recorded sounds)

Nonspecific musical effects• Musical themes for characters or scenes• To create or reinforce a psychological mood or

feeling

Effects

Barking dogs, telephones, doorbells, train whistles, etc.Background or ambient sounds• Wind, people talking in a bar, street noises,

etc.

Provide clues to location and time period

Reinforcement

Use microphones to boost loudness level of actor’s voicesAcoustics: The sound transmission characteristics of a room, space, or material; also the science that studies those qualitiesMix and Balance voices with music/sound effects• To adjust the loudness and equalization levels of individual

signals while mixing, to achieve an appropriate blend

Nature of Sound

Sound is a pressure wave that moves through the air FrequencyIntensityTimbre

Frequency

the rate at which an object vibrates Measured in hertz (Hz)Pitch is the characteristic tone produced by a vibrating body; the higher frequency of vibration the higher the pitchAs frequency increases, pitch increases

Higher Frequency=Higher Pitch

Intensity

Loudness of a sound aka amplitudeMeasured in decibels (dB)Loudness can change without affecting pitch/frequency

Timbre

The distinctive quality of sound that makes one voice sound different from another or a trumpet sound different from a violinBased on the harmonics of the sound-producing body• Frequencies that are exact multiples of a

fundamental pitch or frequency

Harmonics

Basic Acoustics

Acoustics is the science that studies the absorption and reflection of soundIn theatre, the qualities of the stage and auditorium space that affect the audience’s hearing and understanding of the sound (language and music) of the play.

Acoustics

Shape of walls: If walls are parallel, sound will reverberate, or bounce back and forth between them (to reflect in a series of echoes) reducing intelligibility of words• Curve or slant walls to reduce

Finishing/surface of walls: Hard surfaces reflect sound (wood, metal, plaster)• Soft or open-surface materials absorb sound

(cloth, foam, insulation)

Acoustics

Music sounds better with more reverberationSpeech requires short reverberation Challenge of designing acoustics of a space that is used for both music and speech• Adjustable spaces• Highly complicated and sophisticated sound

system

Sound Production

Basic Sound System ConfigurationSound-system EquipmentRecording and Playback Equipment

Basic Sound System Configuration

Sound is picked up by a transducer, i.e. a microphone The transducer converts mechanical energy (sound wave) into electrical energy (electrical signal)Electrical signal is sent to an amplifier which boosts (amplifies) the power of the electrical signalElectrical signal is sent to a speaker, which converts the electrical energy into mechanical energy (sound waves) which reaches our ears

Basic Sound System Configuration

To control the tone (bass through treble frequencies) use an equalizer, which modifies the signal coming from (microphone) or to (speaker) a transducer

Sound System

Mechanical Sound Microphone (transducer)

Electrical Sound Preamp Equalizer

Storage device/ playback Equalizer

Amplifier Speaker (transducer)

Mechanical Sound Ear

Sound-System EquipmentLoudspeaker and speaker system• Loudspeaker is a transducer that converts the

electrical energy of the signal to a mechanical energy (waves) that we can hear

• Electrical signal activates a magnet which moves back and forth creating vibrations in the speaker cone

• Woofer (low-frequency), mid-range speaker, tweeter (high-frequency)

• Speaker cabinet is designed to enhance the reproduction of a specific frequency

Sound-System EquipmentPower Amplifier• Boosts the low-voltage input signal from input

source (mic, cd player) to a higher-voltage output signal capable of driving loudspeakers

Equalizer• Boosts or attenuates (decreases/lessens)

portions of the signal to affect the loudness of the specific segments of the sound spectrum

• Similar to the bass/treble controls on your car or home stereo

Sound-System EquipmentPreamplifier• An electronic device that raises the output of a

low-level signal so that it can be read and processed, without distortion, by the next piece of equipment in the sound system

Mixers• Devices used to mix the output from a variety of

sources and route the blended signal on to other devices

• Assignable channels for mics, cd, computer, etc.

Sound-System Equipment

Patch Bay• Used to cross-connect between the various

pieces of equipment (CD player, computer, equalizers, amps, speakers)

• Outputs and inputs for each piece of equipment are connected to the corresponding receptacles on the patch panels

• A patch cord connects output of one piece of equipment to the input of another

Recording and Playback Equipment

MIDI (Musical Instrument Digital Interface)• Allows synthesizers to communicate with each

other, the communication language used between various types of digital equipment used in theatre sound

Computer• Used in every function: recording, editing,

storage, playback, and show controlCD/Tape• For recording and playback

Recording and Playback Equipment

Microphone• Dynamic mic: very good frequency response,

rugged, most commonly used in theatre sound• Condenser mic: excellent frequency response,

reasonably rugged, highest-quality• Needs a power supply (phantom box)

• Microphone pick up patterns• Omnidirectional (wireless mics)• Directional: cardioid (front pick up only),

hypercardioid (front and rear pick up)