Doubts on harmony

[flyin'_fingers]

I just composed a lick, an I started it out in the E note. Then I decided to put a harmony line over it, and i thought a line starting at A sounded really good. I counted the tones in between(i dont know if that's the correct way to say it) and it comes up to a total of
3 1/2. Now, if i counted right, would this make it a "Perfect 5th" or a "Diminished 6th", or are they the same? If not, how do I know when it'll be a perfect 5th and a dim 6th if they both have the same amount of tones?

[gck]

hmm, that's wrong, E-A is a perfect 4th: E - F - F# - G - G# - A -> 5 halfsteps. The perfect fifth would have been E-B. However, P4 and P5 are each other's inverted intervals, so if you'd start on an A below the E, that would be a P5!

Well, how to spell intervals? That's a bit tricky:

You have to understand scale degrees: in a (diatonic) scale, every note gets a certain degree in relation to the root, which has the degree 1. In major and minor scales, for example, all the degrees also have names, which are (I'll take C major as example)

Cmaj Degree Name
C 1 Tonic
D 2 supertonic
E 3 mediant
F 4 subdominant
G 5 dominant
A 6 submediant
B 7 leading tone

(If there's not a halfstep between the 7th and the tonic, like in a nat. minor scale, the 7th is called subtonic because it doesn't "lead" into the tonic that much then...)

Together with the halfsteps between two notes those make up the correct interval spelling. The "second" part of the interval name (fifth, sixth, fourth) is decided by the scale degree of the two notes. That would be

Tonic - Tonic Prime, Unison
Tonic - supertonic Second
Tonic - mediant Third
Tonic - subdominant Fourth
and so on...

In the C major scale, for example, any interval between a C and any G would be a fifth because of the scale degrees. Any C to any E would be a third, for the same reason, and so on...

The "first" part of the interval spelling comes from the halfsteps, like perfect, major, minor, augmented, etc...

An example: C - G
1) We know that G is the fifth scale degree to C, so it's definitely a fifth.
2) And there are 7 halfsteps between those two, so it's a perfect fifth.

Another one: A - Eb
1) Again, the fifth scale degree, so it's a fifth.
2) However, between the two notes are just 6 halfsteps, so it's not a perfect but a diminished fifth.

Now the tricky bit: A - D#
1) D to A is the fourth scale degree, hence a fourth!
2) A - D# has 6 halfsteps again, but because of 1) we have to call it augmented fourth this time. Even if it sounds the same as A - Eb, A - D# is a completely different interval. That is called "enharmonic" spellings.

(Note that an interval of 6 halfsteps is called a tritone, but that isn't really an interval name. For example, you wouldn't call something a dimished tritone or an augmented tritone because a tritone is not composed of certain scale degrees: the "real" name of a tritone will always be either an aug. 4th or a dim. 5th)

I hope you can understand all this, but if not, don't hesitate to ask again!

[Josh Redstone]

I like harmonizing in fourths, but could you give me some suggestions on what else sounds too? Thanx.

[gck]

Play around with open voiced intervals as well: that means that the root note and the harmonized note are not in the same octave.

Or harmonize something using major or minor thirds or sixths, depending on what note would fall into the scale. That can sound pretty interesting too because of the minor/major interval difference...

Just play around a bit and look what you can come up with: it's a good idea to just try new things without worrying about the theory, and when you find a sound you like, then use your knowledge of theory to find out why it is so, so that you can out it into your "idea bag" for your improvisation!

[Josh Redstone]

I would experiment, and try to find what sounds good, but the other guitarist in my little band that I got going isn't much of a lead player, so I need to worry about theory if I'm composing something.
Those open voiced intervals sound like a good idea. I'll try them. Thanx.

[Jools]

what the ... ?

and you guys actually know what you're talking about?

[Josh Redstone]

Buh?

[gud4nothing]

thanks josh, i've learned so much from that.

[Josh Redstone]

I didn't know I said anything intelligent.

[gud4nothing]

oh, that was meant for gck( i think). sorry.:(

[Andrew]

Thirds and sixths sound food but you have to worry abuot major and minor. Not like fourths.