Sorry Zeppelin, I didn't mean to confuse you man. I apologize, I'll try to clear it up anyways. When you say triangle, I'm guessing you mean a triad. (A three note chord) If I am wrong or you don't get it don't worry about it. In this case B, D, F is a diminished chord, and when adding an Ab to the mix. It's a minor 7th above the root B. So the spelling becomes Bdim7 (the minor is understood, so it is not written) or as you wrote, A Diminished Septa. It's probably just that the book uses a different termanology. Both are right!
Ok now when talking about steps in the scale. It's just like counting up the letters in a MAJOR SCALE PATTERN (M, M, m, M, M, M, m). Each number is a different letter in the scale. This is probably better explained in a few examples.
In C maj the notes are C, D, E, F ,G, A, B. The formula of the major scale is 1, 2, 3, 4, 5, 6, 7. C=1, D=2, E=3, etc. Got it?
Now use the key of C minor it's C, D, Eb, F, G, Ab, Bb. The formula of the minor scale is 1, 2, b3, 4, 5, b6, b7 etc. C=1, D=2, but the third note is one step lower in the minor scale so it's written b3=Eb. And so on.
Hopefully you got it, if not just think about for a second.
Here's the full key starting with C... C=1, C# =#1, Db= b2, D= 2, D#= #2, Eb= b3, E=3, F=4, F#= #4, Gb= b5, G=5, G#= #5, Ab= b6, A=6, A#= #6, Bb= b7, B= 7, C=8, and on and on.
Now it's the same thing with chords, 1 represents the root of the chord instead of the key note (C = Cmaj).
In C diminished its 1, b3, b5. Looking at the key above the the notes are C, Eb, Gb. That's how it works. You better understand it now ;) just kidding. If you still are having problems, let me know I'll help you. As for a site on the net about theory, wouldn't know. I got it all from either books, music teacher, or family. But Im sure someone on here knows a place. I hope this helps, latr.
P.S now when you look at the key i wrote, you should see why the 4th note isnt called a 6th instead a 7th. You probably remember why, now that you see it. Hopefully I refreshed your mind on how it works.
[Edited by noticingthemistake on 12-26-2002 at 11:47 PM]
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