The crest factor is a measure or possibility of the dynamics to measure an audio signal. It indicates how much the amplitude (volume) of the audio signal fluctuates and is converted into dB (decibels) measured. The crest factor is calculated by taking the peak value (the highest Amplitude) of the audio signal by the mean (average amplitude) of the audio signal. The crest factor is a factor used to judge the quality of audio as it directly affects the dynamics and tonal balance of the signal. A high crest factor means that the audio signal has high dynamics and that the amplitude of the signal varies greatly, which is not always a bad thing (e.g. with classical music). On the other hand, a low crest factor means that the audio signal has less dynamics and that the amplitude of the signal fluctuates less (e.g. with Metal ode electronic music). The crest factor is a useful tool in music mastering, since it dem mastering engineer allows to adjust the dynamics of the audio signal and improve the tonal balance. However, it is important to note that crest factor can vary based on genre and preference, and that there is no "right" crest factor setting.