[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: do these notes exist?
From: |
Hans Aberg |
Subject: |
Re: do these notes exist? |
Date: |
Mon, 24 Mar 2008 19:52:21 +0100 |
On 24 Mar 2008, at 19:11, Michael David Crawford wrote:
I learned a scale with double-sharps just the other day. Let me
see... Key of A# Minor. From Scales and Arpeggios for Keyboard by
Palmer, Manus and Lethco, page 52:
A# Harmonic Minor:
A# B# C# D# E F# G## A#
A# Melodic Minor, Ascending:
A# B# C# D# E F## G## A#
Now, F## is G natural, and G## is A natural. But my understanding
for the odd double-sharp and double-flat notation is that
convention calls for every letter - ABCDEFG - to be present in
every key, with enough sharps or flats added to make the intervals
right.
It is not merely a convention (except in 12-ET, see below) - it
becomes that way in a temperament other than 12-ET.
Write the pitches in the circle of fifths:
Fbb Cbb Gbb Dbb Abb Ebb Bbb
Fb Cb Gb Db Ab Eb Bb
F C G D A E B
F# C# G# D# A# E# B#
Fx Cx Gx Dx Ax Ex Bx
here written the on several rows: left/down.
Then transposition in fifths moves set of pitches left/down. So, for
example A harmonic minor consists of the pitches A B C D E F G#. To
transpose A A #, just move the whole set down one step.
Without that convention, the harmonic minor would be:
A# C C# D# E F# A A#
So you see, C and A would occur twice, but with different
accidentals. That would probably be confusing in an actual score if
it was notated that way.
In dedicated 12-ET music, it odes not matter how one writes it. But
in often, instruments are expect to adjust towards a temperament
where it matter, in Western music, Just intonation. So in such case,
enharmonic equivalence is not formally applicable.
Also, the notational system does not derive from 12-ET, so if one
does not adhere to what is a convention in this temperament then, one
may have to throw in some extra temporary accidentals.
Hans Ã…berg
Re: do these notes exist?, Damian leGassick, 2008/03/24
Re: do these notes exist?, Hans Aberg, 2008/03/24
Re: do these notes exist?, Ledocq-Boccart, 2008/03/27