Title: The Avoidance of Part-Crossing in Polyphonic Music:
1The Avoidance of Part-Crossing in Polyphonic
Music Perceptual Evidence and Musical Practice
David Huron
Presented by Zhenyao Mo
2Dowlings Observation
Two Concurrent interleaved melodies
Transpose
Without pitch overlay
Part Crossing
Easy to segregate
Hard to segregate
3Three Hypothesis
Pitch Domain
Time Domain
Tessitura
Range Overlap
Local Crossing
4Two Questions
- Is the avoidance of part-crossing on purpose or
just because the different pitch distributions
for various voices? - Is the purpose of such avoidance to prevent the
sort of perceptual confusions, say, can not
segregate different parts?
5Subjects 105 polyphonic keyboard works by Bach
Why???
- As for choral works, different parts have their
own instrumental or vocal range, while keyboard
music parts are relatively free to traverse whole
range - In keyboard music the parts maintain homogeneous
timbers
6Measurement of Part-Crossing
- Sonority each novel vertical pitch arrangement
between two voices can be deemed a distinct
sonority - Degree of part-crossing proportion of vertical
sonorities in which a part crossing has occurred
7Some Facts
Number of Parts Two Three Four Five Six
Degree of part-crossing Mean () 0.18 0.79 1.78 3.11 6.11
Standard Deviation of Pitch 5.65 4.71 4.47 4.33 3.94
8Auto-Phase Method
Aim To distinguish Local crossing from
tessitura and range overlap
Basic idea keep the pitch range, but regenerate
the order or correspondence
9More Facts
10More Facts
11Two Questions
- Is the avoidance of part-crossing on purpose or
just because the different pitch distributions
for various voices? - NO
- Is the purpose of such avoidance to prevent the
sort of perceptual confusions, say, can not
segregate different parts? - YES, we got evidence.
12Thank You