The professional terms in music evaluation include pitch, polyrhythm, beat, rhythm and timbre.

1. Pitch

Pitch refers to various sounds of different levels, that is, the height of the sound, one of the basic characteristics of the sound. The pitch of the sound is determined by the vibration frequency, and the two are positively correlated: if the frequency (that is, the number of vibrations per unit time) is high, the sound is "high", and vice versa.

2. Polyrhythm

Asymmetric rhythm (asymmetric rhythm) is also called "polyrhythm" (polyrhythm). In the same phrase or measure, the rhythm of each part is inconsistent; Or in the same section, the duration of each beat is inconsistent. Broadly speaking, polyphonic music belongs to the strange rhythm used by modern composers, and it is a highly complex rhythm.

3. Beat

Beat is a unit for measuring rhythm. In music, a series of beats with certain strengths and weaknesses appear repeatedly at certain intervals. Such as 2/4, 4/4, 3/4 beats, etc. Beat is an organizational form in a piece of music that expresses fixed unit duration and intensity patterns.

4. Rhythm

Combine a disordered beat stream into different patterns, integrate different parts of different lengths that are often repeated, and progress musical melody in scales, notes or syllables length, strength, etc. The rhythm of music is often compared to the skeleton of music.

5. Timbre

Timbre (Timbre) means that different sounds always have distinctive characteristics in terms of waveforms, and different objects vibrate with different characteristics.

Different sound emitters have different timbres due to their different materials and structures. For example, the sounds produced by pianos, violins, and people are different, and the sounds produced by each person are also different. Therefore, timbre can be understood as the characteristics of sound.