Talk:Shimmerstep

Why the average beat rate of voice vibrato falls between 4.5–6.5 cycles per second

The simplest answer is that it physically practically has to. And this is so because the major muscles in the vocal tract will not vibrate at frequencies above 8 Hz: There are three different voice vibrato processes that occur in different parts of the vocal tract. Peter-Michael Fischer has vibrato types defined by place of production:

• The vocalis muscle vibrates at a frequency of 6.5 to 8 Hz.
• The diaphragm vibrates at a frequency below 5 Hz vibrato
• A combination of the two, resulting in a vibrato whose frequency is between 5 and 6.5 Hz. Fischer writes:

"This combination is relatively stable in the most beautiful voices. An important feature is that the partial functions can appear during the song as "accents": In the context of the presentation expressive wave dominates respirativa, lyrical character, but in an accelerated, or glottis wave, hard feature heroic, but in a slow way."

— Peter-Michael Fischer. The upper limit of vocalis muscle vibration at 8 Hz may be not entirely arbitrary, but related to the theta wave human neural oscillation, which is centered in the hippocampus, and whose rhythm has a frequency of 5 to 8 Hz over the combination of the hippocampus and the regions of the brain (most directly) connected to it. Instrumental vibrato lacks this type of hard upper frequency limit, but studies of the vibrato rates in string playing since the 1930s have repeatedly affirmed that the most typical frequency range is nevertheless similar, at 5 to 7 Hz.--Moremajorthanmajor (talk) 01:51, 27 November 2024 (UTC)