Re: tonus diabolicus! (Was: SRV)

Rufus expounded in BijMm.132868$5n1.32093@attbi_s21:">news:BijMm.132868$5n1.32093@attbi_s21:

Tim C. wrote:
On Mon, 16 Nov 2009 06:49:06 -0800 (PST), Pt wrote in post :
<news:7f99d3b8-0f83-4295-a93b-d23562803790@xxxxxxxxxxxxxxxxxxxxxxxxxxx
m> :

Blue notes.

Work of The Devil!

...tonus diabolicus!

Since I've been doing music theory with my
broken wing, I was asking my teach
about how to easily identify tritones in
standard notation. For major keys, he said
there is only one between the 4th and 7th
(excluding notes with accidentals).

So then it must follow that in the relative
[natural] minor, you'd find them at 6 and 9/2.
This is because the same two notes are involved,
axcept that A becomes root (#1) in Am.

C: 12345678
ABCDEFGABC
Am: 123456789

IOW, in C/Am the diabolicus notes are F and B.

Interestingly, it doesn't matter if it is 6-9
or 2-6 (they are equal sized intervals). That
also means 4-7 or 7-4 are likewise the same in
major.

Have I got this right?

If so, it makes identifying these easier in
written music.

Obviously, things are trickier for other
minor scale forms.

nark
.