Music Technology 112

compression

The region in a sound wave where particles are pushed together, increasing pressure.

propagation

The way a sound wave travels through a medium.

rarefaction

The region in a sound wave where particles are spread apart, decreasing pressure.

compression wave

A wave in which particle displacement is parallel to the direction of wave propagation (e.g., sound).

transverse wave

A wave in which particle displacement is perpendicular to the direction of wave propagation.

resonance

The amplification of a sound when a system vibrates at its natural frequency.

pinna

The outer part of the ear that collects sound.

ear canal

The tube leading from the pinna to the eardrum.

eardrum

A membrane that vibrates in response to sound waves.

ossicles

Three tiny bones in the middle ear that transmit sound from the eardrum to the inner ear.

Eustachian tubes

Tubes that equalize pressure between the middle ear and the atmosphere.

oval window

A membrane that connects the middle ear with the inner ear.

cochlea

A spiral-shaped organ that converts sound vibrations into electrical signals.

basilar membrane

A structure in the cochlea that helps detect pitch.

organ of Corti

The sensory organ in the cochlea that contains hair cells.

music perception/psychoacoustics

The study of how we perceive sound and music.

music cognition

The study of mental processes involved in understanding music.

waveform view

A visual representation of audio showing amplitude over time.

pitch

The perceived frequency of a sound.

frequency

The number of vibrations per second of a sound wave, measured in Hertz (Hz).

hertz (Hz)

Unit of frequency, representing cycles per second.

period

The time it takes for one cycle of a wave to occur.

ultrasonic

Sound frequencies above human hearing (>20 kHz).

infrasonic

Sound frequencies below human hearing (<20 Hz).

Shepard tones

An auditory illusion of a tone that continually ascends or descends in pitch.

loudness

Perceived intensity of sound.

amplitude

Height of a wave, related to volume.

decibels of sound pressure level (dB SPL)

A logarithmic unit measuring sound intensity.

threshold of hearing

The quietest sound the average human ear can detect.

threshold of pain

The sound level that causes physical pain (around 120–130 dB SPL).

temporary threshold shift

Temporary hearing loss after exposure to loud sounds.

timbre

The quality or color of a sound that distinguishes different sources.

waveform

The shape of a sound wave as it appears in a graph of amplitude over time.

sine wave

A pure tone with only one frequency component.

triangle wave

A waveform with odd harmonics that sounds hollow and smooth.

sawtooth wave

A waveform with both odd and even harmonics; sounds buzzy or bright.

square wave

A waveform with only odd harmonics, sounding hollow or woody.

pulse wave

A waveform similar to a square wave but with varying duty cycles.

noise

A signal with random frequencies.

white noise

Noise with equal intensity across all frequencies.

pink noise

Noise with equal energy per octave; sounds smoother than white noise.

articulation

The way in which a musical note is executed (e.g., staccato, legato).

amplitude envelope

Describes how a sound’s amplitude changes over time.

attack-decay-sustain-release envelope (ADSR)

A common envelope used to shape sound over time.

attack-release envelope (AR)

A simpler envelope with only an attack and release phase.

rhythm

The timing of musical sounds and silences.

transient patterns

Short bursts of sound that signal the beginning of an event.

beat detection

Analyzing audio to determine the timing of beats.

overtone series

The sequence of pitches above a fundamental frequency.

fundamental frequency

The lowest frequency of a sound.

overtones

Higher frequencies that occur along with the fundamental.

harmonics

Whole-number multiples of the fundamental frequency.

partials

Individual frequency components of a sound.

Pythagorean comma

A small pitch difference due to tuning systems.

equal temperament

A tuning system where each semitone is spaced equally in pitch.

spectrum view

Displays audio frequency components visually.

spectrogram view

A visual representation of sound showing frequency, amplitude, and time.

waterfall spectrum

A 3D representation of a spectrogram over time.

Fourier’s theorem

Any complex waveform can be broken down into sine waves.

harmonic spectra

A frequency spectrum consisting of harmonic overtones.

inharmonic spectra

A spectrum with overtones that are not whole-number multiples of the fundamental.

inharmonicity

The degree to which overtones deviate from whole-number multiples.

equalization (EQ)

The adjustment of frequency levels in audio.

cut

Reducing a frequency band using EQ.

boost

Increasing a frequency band using EQ.

graphic equalizers

Devices with sliders for adjusting frequency bands.

transducer

A device that converts energy from one form to another (e.g., sound to electricity).

microphone

A transducer that converts sound into an electrical signal.

preamplifier (preamp)

Boosts a microphone-level signal to line level.

analog to digital converter (ADC)

Converts analog audio to digital data.

audio interface

A device that connects audio gear to a computer.

digital domain

The realm where sound is represented by digital data.

digital to analog converter (DAC)

Converts digital audio back to analog.

amplifier

Increases the power of an audio signal.

speaker

Converts electrical signals into sound waves.

powered speakers/active monitors

Speakers with built-in amplifiers.

dynamic microphone

A durable mic that works via electromagnetic induction.

capsule

The part of the mic that captures sound vibrations.

small/large diaphragm

Refers to mic diaphragm size, affecting sound sensitivity.

ribbon microphone

A mic using a thin metal ribbon to capture sound; sensitive and smooth.

condenser/capacitor microphone

Uses capacitor plates to detect sound; requires power.

phantom power

Power supplied through an XLR cable to condenser mics.

electret microphone

A type of condenser mic with a permanently charged diaphragm.

USB microphone

A mic that connects directly to a computer via USB.

wireless microphone

A mic that transmits audio via radio signals.

polar pattern

The directional sensitivity of a microphone.

end-address/side-address microphone

Describes the direction from which the mic is addressed.

omnidirectional pattern

Picks up sound equally from all directions.

bidirectional (figure-8) pattern

Picks up sound from the front and back, not the sides.

cardioid/hypercardioid patterns

Heart-shaped patterns focusing on sound from the front.

trim/gain knob

Controls the input level of an audio signal.

pad

Reduces input signal level to prevent distortion.

signal levels

Describes the strength of audio signals (mic, line, etc.).

mic level

Very low-level audio signal from a microphone.

balanced signal

A signal with two opposite polarity lines to reduce noise.

XLR connectors

Common balanced audio connectors.

balanced cable

A cable carrying a balanced signal to reduce interference.

line level

Standard signal level for professional audio equipment.

TRS (tip-ring-sleeve) connectors

Used for balanced or stereo signals.

unbalanced signals/cables

More susceptible to noise; carry signal and ground only.