Editing Pitch (music) (section)

===Just-noticeable difference===

The ''[[just-noticeable difference|just-noticeable difference (jnd)]]'' (the [[Sensory threshold|threshold]] at which a change is perceived) depends on the tone's frequency content.  Below 500&nbsp;Hz, the jnd is about 3&nbsp;Hz for sine waves, and 1&nbsp;Hz for complex tones; above 1000&nbsp;Hz, the jnd for sine waves is about 0.6% (about 10 [[Cent (music)|cents]]).<ref>
{{cite book
 | title = Springer Handbook of Speech Processing
 |editor1=Jacob Benesty |editor2=M. Mohan Sondhi |editor3=Yiteng Huang |author1=Birger Kollmeier |author2=Thomas Brand |author3=B. Meyer  |name-list-style=amp | chapter = Perception of Speech and Sound
 | publisher = Springer
 | year = 2008
 | isbn = 978-3-540-49125-5
 | page = 65
 | chapter-url = https://books.google.com/books?id=Slg10ekZBkAC&pg=PA65
 }}</ref>
The '''jnd''' is typically tested by playing two tones in quick succession with the listener asked if there was a difference in their pitches.<ref name=Olson>{{Cite book|title=Music, Physics and Engineering |last=Olson |first=Harry F. |author-link=Harry F. Olson |year= 1967|publisher=Dover Publications |isbn=978-0-486-21769-7 |pages=171, 248–251 |url=https://books.google.com/books?id=RUDTFBbb7jAC }}</ref> The '''jnd''' becomes smaller if the two tones are played [[simultaneity (music)|simultaneously]] as the listener is then able to discern [[Beat (acoustics)|beat frequencies]]. The total number of perceptible pitch steps in the human hearing range is about 1,400; the total number of notes in the equal-tempered scale, from 16 to 16,000&nbsp;Hz, is 120.<ref name=Olson/>