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Diminished ( Whole - Half ) scale intervals question

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#1 lettuce

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Posted 22 May 2018 - 18:20

I want to correctly describe the intervals, counting up from the root note to each of the scale degrees in the diminished ( whole - half ) scale. This is what I have so far, I'm not so sure if its right.

 

C DIMINISHED [ WHOLE - HALF ] :

 

R    W   H    W    H   W     H     W   H

 

R    M2 m3 P4   d5  m6    d7   M7  P8

 

1    2    b3    4    b5    b6    6    7     8

 

C   D    Eb   F    Gb   Ab    A    B    C

 

I used flats because the scale degrees have been flattened in the scale formula.

 

There are 8 notes in the scale before the octave so I cant describe the intervals just as intervals numbered 1-7 as usual.

There must be one double number. Also there is a double lettered note name ( 'Ab' AND 'A' ) which is unusual.

 

I went for 'diminished 7th' AND 'Major 7th'.

 

Is that right?

 

Or should I have used 'minor 6th' AND 'Major 6th', onward to 'Major 7th' and 'Perfect Octave'?

I have a feeling that might be the right way because there is a 'b6' AND a '6' in the scale formula ( unusual because there are two 6th degrees of the scale ).


Edited by lettuce, 22 May 2018 - 18:30.


#2 radian

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Posted 28 May 2018 - 22:23

Diminished 7 is the right name for the A in this case.

( If you were playing chord the A would the 7th )



#3 lettuce

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Posted 29 May 2018 - 02:52

Diminished whole-half scale.

Its a weird one.

I thought 'A' must be diminished 7th too, because 9 semitones is a diminished 7th interval and because 'A' is the seventh scale degree.

Naming 'A' as diminished 7th would lead to interval naming ( from root note to each scale degree )  including two '7' intervals.

There must be two of some interval as diminished whole-half has 8 note before the octave instead of the usual 7 notes before the octave, as in the more traditional scales.

 

After some time had passed I looked back at the scale formula ( 1 2 b3 4 b5 b6 6 7 8  ) and noticed that there is both a 'b6' ( flattened sixth ) and and '6' ( Normal / Major sixth ) so instead of using diminished 7th, I went with Major sixth. Diminished 7th and Major 6th intervals both have 9 semitones. After changing it it looks like this ( I put number of semitones in this time around, in the second row ):

 

R   W   H   W    H      W      H    W    H

 

0    2     3    5     6      8       9    11    12

 

R    M2 m3 P4   d5    m6   M6   M7  P8

 

1    2    b3    4    b5    b6    6    7     8

 

C   D    Eb   F    Gb   Ab    A    B    C

 

I don't know if there is any logic to it at all, but at some point in time classical people must have decided to 'double up' the sixth interval in diminished scales ( rather than any interval of their choosing ). This is my assumption based on looking at the scale formula.

 

They want to describe everything in terms of 7 scale degrees because it fits nicely with their traditional view of music ( the seven modes ).

 

As diminished has 8 scale degrees before the octave, rather than seven, it was probably considered to be devilish or something.

It does sound quite 'vampiric' like 'transylvania' or something like that.

 

I think you are right about describing the 'A' as a diminished 7th in the context of a 7 chord. With diminished meaning 'reduced by two semitones'. The seventh degree of C Major scale is B, reduced by two semitones to Bbb, B double flat ( which is an A ). Looking at that, it makes me think my scale formula may be wrong. I'm seriously confused by this.

 

c-diminished-7th-chord-intervals-on-pian


Edited by lettuce, 29 May 2018 - 21:06.






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