Music glossary

A
Note of the scale.

A440
(440 cycles per second) is commonly used for tuning the orchestra.

A due corde
It.: "on two strings". In piano music this indicates the release of the soft pedal.

A prima vista
It.: "at first sight".

A tempo
It.: "in time". Back to the original tempo.

A tre corde
It.: "on three strings".

Absolute pitch
The name given by psychologists to what musicians call 'perfect pitch'. The ability found in a minority of listeners, where the pitch of a tone can be accurately identified without relying on an external reference.

Accelerando
It.: "accelerate". Increase tempo gradually.

Accompaniment
Musical part or parts with a supporting role.

Ad libitum
Lat.: "play freely". In classical music this means free tempo and dynamics, in jazz, pop, rock etc. it means an improvised solo.

Adagio
It.: "slow".

Affettuoso
It.: "with feeling".

Agitato
It.: "agitated". Restless and wild.

Agogic
Subtle tempo and rhythm changes as a part of phrasing.

À capella
It.: singing without instrumental accompaniment.

Air
It.: "Aria". A simple tune.

Al fine
It.: "to the end".

Alfabeto
A system developed by Spanish 17th century guitarists for noting standard guitar chords.

Alla breve
"Shortened time". 2/2 time.

Allegretto
It.: diminutive form of allegro. A little slower than allegro.

Allegro
It.: "fast and lively".

Allegro assai
It.: "very fast".

Allegro moderato
It.: "moderately fast". Fast, but not as fast as allegro.

Allegro non troppo
It.: "fast but not too much".

Amplitude
The magnitude or strength of a signal. The degree of excursion about an average or equilibrium value exhibited by some oscillating quantity. For a vibrating object, amplitude may be expressed in terms of the velocity of the object in space or the pressure it exerts or other physical quantity. Amplitude is commonly measured by one of three methods: (1) the difference between the maximum excursion and the equilibrium point ('peak amplitude'), (2) the difference between the maximum positive and maximum negative points of excursion ('peak-to-peak amplitude'), (3) the standard deviation of all values ('RMS amplitude'). For signals of audible frequency, amplitude corresponds roughly with our perception of loudness.

Amplitude Modulation
(AM). The varying of the amplitude of a signal, usually repetitively. For signals of audible frequency, amplitude modulations in the range of 1 Hz to ~15 Hz evoke a tremolo effect.

Andante
It.: "slow".

Andante moderato
It.: "moderately slow". Slow, but not as slow as andante.

Andante sostenuto
It.: "slow and sustained". Slower than andante.

Andantino
It.: diminutive of andante. Slow, but not as slow as andante.

Animato
It.: "animated", "with movement".

Aria
It.: "song". The word is especially used for solo songs in operas.

Arietta
It.: a small aria.

Arousal compatibility preference
Listeners tend to prefer music that matches their pre-existing arousal level. When asleep most people have a low tolerance for music, especially when the music has a high level of stimulation. Conversely, when in a highly aroused state, most listeners find sedate music to be uninteresting or inappropriate.

Atonal music
Music with no defined key or root note. The term is especially associated with serial music.

Attacca
Go on to the next section without repeat or pause.

Attenuate
To lessen; especially to lessen the amplitude of a signal. When audio signals are attenuated, typically a decrease in loudness occurs. However, attenuation need not always affect loudness -- f.e. the attenuation of a vibrato will result in a lessening of the depth of the vibrato.

Audio frequency
Any frequency audible to the human ear. The range of audio frequencies is usually considered to lie in the region between 20 hertz and 20,000 hertz. However, the specific range of audio frequencies varies considerably from person to person especially with respect to age.

Auditory evoked potential
When an isolated sound is heard, millions of neurons in the auditory cortex are activated. The near simultaneous firing of large numbers of neurons induces electrical potentials that can be measured with electrodes on the scalp. Auditory signals activate regions of the temporal lobes located just above the ears. Because the resulting electroencephalographs (EEG) arise in response to a single sound, they are referred to as auditory evoked potentials or auditory evoked responses.

Auditory induction
The subjective impression of a continuing sound, even though the sound is entirely absent. When a pure tone is alternated with broad-band noise, the tone will appear as a continuous background tone with the noise over-layed. In ideal circumstances auditory induction has been measured for as long as 30 seconds.

Auditory streaming
The subjective sense of connectedness where two or more successive sounds appear to arise from the same sound generating source.