Originally Posted by: gmixstudioswhy is it called equal tempered scale if some notes have no black note in between? :eek:
Equal temperament means dividing the octave in
12 equal half steps. Every half step is separated by exactly the same amount - the ratio of the twelfth root of two.
http://en.wikipedia.org/wiki/Equal_temperamentAs opposed to just intonation (and other systems) that divide the notes in between the octave in
unequal amounts.
http://en.wikipedia.org/wiki/Just_intonationEqual temperament makes it possible to modulate, transpose and harmonize across the range low to high of possible musical tones.
Equal temperament does have "black notes" in between some notes. Consider the chromatic scale:
A
A# (or) Bb
B
C
C# (or) Db
D
D# (or) Eb
E
F
F# (or) Gb
G
G# (or) Ab
The sharps and flats are "black notes" on the piano. But here is where the crucial distinction comes into play.
In equal temperament the musical distance between one note and the next is a half step.
In just intonation the musical distance between one note and the next is also a half step.
However ...
In equal temperament the physical-acoustic distance (measured in hertz - cycles per second of the sound wave of each note) between each of these is exactly the same: one times the twelfth root of two.
In just intonation the physical-acoustic distance (measured in hertz - cycles per second of the sound wave of each note) between each of these is
different from note to note for some of the half steps. This makes for a very inconsistent system.
Make sense?
Christopher Schlegel
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