Hi All,
I really don't understand when to call a interval a major, minor, perfect,ect.
Thank you.
BTW do you know the major scale??? I'll do it in the c major key/scale. I'm assuming you know how to form this. If you dont then tell me and I'll help with that.
1) root note - c
2) 2 steps up - major 2nd - d
3) 4 steps up - major 3rd - e
4) 5 steps up - perfect 4th - f
5) 7 steps up - perfect 5th - g
6) 9 steps up - major 6th - a
7) 11 steps up - major 7th - b
8) 12 steps up - perfect 8th - c

Also to help you understand this even more go to this http://www.musictheory.net/lessons/html/id31_en.html you will see that each of the intervals from the root note in the major scale is either perfect or major (Just class perfect as major, I don't know why they are called perfect). The point I was getting to, to remember what the intervals are just write out the major scale and for perfect intervals (There is no major or minor intervals for perfect ones) add 1 to get the augmented form and -1 to get the diminished form. For major intervals add 1 to get the augmented form, -1 to get the minor form and -2 to get the diminished form.

I hope that helped and if you didn't understand anything then ask and I'll attempt to clarify. I'm sure if I can't then someone else will be able to.
It'll be up as an article soon (hopefully), but reading the attached doc. might help you. Make sure you select the words and paste it into a word document to make it more readable.
Attachments:
Intervals.txt
So are all 4ths, 5ths and octaves perfects??
and all 2nd and 6th majors???

sorry i am just not understanding these at all.

thanks!
Quote by offthewall93
So are all 4ths, 5ths and octaves perfects??
and all 2nd and 6th majors???

sorry i am just not understanding these at all.

thanks!

Yes...

Unisons, 4ths, 5ths and 8ths are perfect, because they only allow 1 "type" (can't express it better) of consonance, while all other types are dissonant.
By this I mean that any perfect interval is consonant, but if you alter said interval, it becomes dissonant right away, that is why they are perfect.

3rds and 6ths are minor/major because they allow 2 types of consonant intervals. Minor 3rds, major 3rds, minor 6ths and major 6ths are all consonant, but if you alter any of them in some other way (diminish or augment them) they become dissonant.
Same for 2nds and 7ths, but these minor/major intervals are dissonant instead of consonant (both are absolute dissonant if I recall correctly, and if you change them you transform them into conditional dissonant intervals). An absolute dissonant interval is an interval whose enharmonical interval is dissonant as well (like 2-bb3), and conditional intervals are intervals whose enharmonical interval is consonant (like #2-b3).

So if you have a m2, it is absolute, since it is enharmonical with #1 (dissonant). M2 is absolute, because it is enharmonical with bb3 (dissonant as well). M7 is absolute, because it is enharmonical with b8 (dissonant). m7 is absolute, because it is enharmonical with #6 (dissonant as well).
But, if you change a major 2nd to an augmented second (#2), you get a conditional dissonant interval (remember it is enharmonical with b3, a consonant interval), and if you diminish it (bb2) it is enharmonical with the unison (1), again consonant.
If you augment the 7th, you get #7, enharmonical with an octave (8, again consonant). If you diminish the 7th, you get bb7, enharmonical with a major 6th (M6, consonant).
That means that 2nds and 7th are absolute dissonant intervals, and if you alter them they transform into conditional intervals, that is why they also allow 2 types of intervals that are both absolute dissonant.

To figure out which interval is enharmonical to which, try finding a keyboard, and find these intervals in the key of C:

C-1 Unison
D-2 Major second
E-3 Major third
F-4 Perfect fourth
G-5 Perfect fifth
A-6 Major sixth
B-7 Major seventh
C-8 Octave

Now, just go up and down black/white keys in the keyboard as all the sharps or flats you have in the interval, and find in which place of the keyboard it falls into, and knowing the note figure out it's enharmonical interval...