The rhythm is in music, which determines the duration of notes to each other. The rhythm, melody, tempo and nuance are the four main facts to characterize a given musical phrase.

In western music, the word means a tone scale music belonging to the tonal system.

• Caught in a broad sense, the word "tone" can refer to the tonal system as a whole.
• The word can also take the direction of height, its fundamental to some instruments.
• The word tone can be used as a synonym for tone.

A tone is defined as the set of intervals, melodic and harmonic as well, between hierarchical levels of a given scale compared to its fundamental level, called tonic. A tone is characterized by both the tonic and its mode.
Each key is constructed from the diatonic scale.

The tone is also a means to locate a musical instrument in relation to C reference.
The flute, violin or piano are in C, that is to say that when the C is played, it really means to do. The B-flat trumpet sounded really flat so when playing a do. The horn (in F) is heard when playing an F do.

The tone is very important because it will allow transposition and transcription of partitions in C in tones of instruments with different pitches.

Some instruments and their tone:

• Ut: Piano, strings, flutes and piccolo, oboe, bassoon, C trumpet, trombone, tuba, bass tuba.
• D flat: the old piccolos.
• Re: Trumpet in D.
• Eb: alto saxophone and baritone, small bugle, horn in E flat, alto (small tuba), clarinet, bass tuba.
• F: Cor.
• Sol: Trumpet in G.
• The: Oboe d'amore, the trumpet.
• Bb: soprano saxophone, tenor tuba (euphonium and baritone), B-flat trumpet, flugelhorn, clarinet, bass tuba (bombardon).