In the context of the quote you provided, the term "normalized" means that the highest amplitude value of the sound (volume peak) is adjusted or scaled to fit within a specific range or standardized scale. Normalization is a common technique used in audio processing and analysis to ensure that different audio signals or notes are comparable or have consistent characteristics.
Specifically, the "volume peak position" is the time location within the note where the highest amplitude value occurs. It represents the moment when the sound reaches its loudest point during the duration of the note. By normalizing this peak position "over the length of the note," it means that the time value is scaled to a relative measure within the duration of the note itself.
For example, let's say we have a musical note that lasts for 2 seconds, and its highest amplitude value occurs at the 1.5-second mark. When normalized over the length of the note, the volume peak position would be represented as 0.75 (1.5 seconds / 2 seconds). In this case, the normalized value is between 0 and 1, indicating the position of the peak relative to the total length of the note.
Normalization is valuable because it allows for consistent comparisons between different notes or sound signals, regardless of their individual durations. This way, researchers and analysts can study and compare sound characteristics more effectively without being influenced solely by the absolute time values of the peak positions.