# Music Theory 1-Intervals

Discussion in 'Guitar Lessons, Tutorials & Tips' started by dennis, Feb 13, 2005.

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1. ### dennisThe Bhangra King

Well ive been on this site for some months and thought id contribute. So im gonna try start a music theory section. In this 1st section im gonna start with Intervals. intervals are the basics to ur music theory, so u better know em bfore u go further...k...lets start!

An interval describes the distance between two notes.
...kidding : (do bear with me!!)

Types of intervals:
Perfect Intervals
Major intervals
Minor Intervals
Now an interval can be only one of the above, that is it can be perfect,major or minor. Not perfect and minor etc.

Now dont u worry..ill be going over all of them.

Perfect Intervals:

Lets take a Cmajor scale=
C(1)--D(2)--E(3)-F(4)--G(5)--A(6)--B(7)-C(8).
(- indicates a half step,i.e a jump from say Cto C# or E to F)
The 1st note C is the root.
The 8th note which again is C is called the Octave.

The Root,4th,5th and the Octave are our Perfect Intervals.
The 4th note is called the Perfect Fourth and the 5th note is called the Perfect Fifth(ie. Perfect 4th w.r.t our root which is C in this case)

Thus we can see that 2 and a 1/2 half steps lead to a perfect fourth and then another 2 steps give u the perfect 5th.
So u can get the Perfect 4ths and 5ths for any root note!

So the Perfect 4th of D is G,E is A, etc
and the Perfect 5th of D is A, E is B and so on.

Major and Minor Intervals:

In a major scale everything that isnt perfect is major!
So again in our Cmajor scale:
C(1)--D(2)--E(3)-F(4)--G(5)--A(6)--B(7)-C(8).
The 2nd(D),3rd(E),6th(A) and 7th(B) are all major.
Hence the are called Major 2nd,Major 3rd etc.
Hence the Major 2nd of C is D and so on.

And finally Minor Intervals: they are half a step behind Major intervals.
Thus the minor 2nd of C is Db, minor 3rd of C is Eb etc.
But beware, u cant say that the minor 3rd of C is D#. That is by rule.
While naming an interval we must include the basic interval note name

Thus u can now get the perfect,major and minor notes for any given root!...yay :rock:

..well thats the end the first part.
We have got 2 alterations left which are known as Augmented and Diminished..ill be talking about them after I take a little break!

2. ### BandbaajaPronounced Band Baaaa Ja

good post, awaiting the future lessons on theory.
Beginners please pay attention to this stuff

3. ### ananth222Beginner

Good info, and reps for u.

If you go half step above the major or perfect note, you get the "augmented" notes
Thus on C, F# is the "augmented fourth"
Similarly, half step below a perfect or minor gives "diminished", thus Gb is "diminished fifth"
But you say F# and Gb are the same? Thats only in equally tempered music (like most western music now)
This is the reason we have so many "Re"s and so many "Ga"s in Indian music.

4. ### dennisThe Bhangra King

Hey thanx Bandbaaja.
Continuing from where I left.

Augmented And Diminished Intervals

Augmented and Diminished are alterations.
Now dont worry if I dont make sense, go on reading.

Augmented and Diminished as an alteration to The perfect Interval:

Augmented raises by half step.
Diminished lowers by half step

Thats kinda like a theorem..so learn it by heart.
Now clearing it up with an example
Lets take our Cmajor scale again
C(Root) D(Major 2nd) E(Major 3rd) F(Perfect 4th) G(Perfect 5th) A(Major 6th) B(Major 7th)

Now our Augmented 4th will mean add half a step to the Perfect Fourth. Thus we have our perfect 4th F, add a half step so we get F#.
And Diminished means lower by a half step, so our diminished 4th becomes Fb(F flat).
Now there may be one doubt..aint Fb=E?..so i shoud be able to right Diminished 4th from C =E?....No!!!!!!
We will only right it as an Fb(even though Fb may be E). This is by rule.
When naming intervals we always name them relative to the basic interval notes name
..its kinda like one of those mathematical axioms.

Augmented and Diminished as an alteration to the Major/Minor Interval:]

Augmented raises a major interval by half step whereas diminished lowers a minor interval(yes minor not major) by half step.

Again from our C major scale:
C(Root) D(Major 2nd) E(Major 3rd) F(Perfect 4th) G(Perfect 5th) A(Major 6th) B(Major 7th)
major 2nd is D
minor 2nd is Db
augmented 2nd=half step+major 2nd=D#
diminished 2nd=minor second-half step=Dbb(yes D flat flat,not C)

Thats pretty much it.
Now there maybe one question lingering in your mind...why in the name of the holiest of holies should I waste my time through such complicated stuff!!!??
Honestly..thats what I thought when i was going through this the first time.
The answer is simple..if u wanna learn how to construct chords(triads) and scales then u gotta first know the above. theres no two ways, learning intervals is a must. So I suggest learn the stuff above.

Possible Exercises:
Write the Perfect 4th,5th Major and Minor 2nds, augmented 4ths,2nds and diminished 4ths,2nds of the A major scale.
The A major scale:
A B C# D E F# G

5. ### SubhroArgentina lost :&quot;(

wow. gr8 tips. 5 stars/reps.

6. ### ananth222Beginner

This is where temperament matters. In equal temperament, all half steps are equally tempered, and there are 12 in an octave. Since the octave note is double the root notes frequency, a half step will be the ratio of 12th root of 2, and constant throughout the scale. In other temperaments, Fb and E will be different notes.

7. ### dennisThe Bhangra King

Im into western music so i didnt know that, thanx for the info ananth.

8. ### jayswamiBlue J

this is western music only equal temperment, pythogoras, natural major etc etc. ever wondered why your open G and B never sounds right to your ears? even after tuning? thats curse of equal temperement for u.

9. ### shakHarrr!

nicely explained dennis...
Augmented and Diminished as an alteration to the Major/Minor Interval
i'll always remeber that ^^
cool post!!

10. ### alericNew Member

Cool post Dennis. Explained really well......

Hoping for more theory posts from you.

11. ### BandbaajaPronounced Band Baaaa Ja

sahi hai sahi hai

12. ### ambujPro Tabber

there are other temperaments? can we have some more info on that?
btw, cool post dennis, really helpful

13. ### dennisThe Bhangra King

thanx guys, ur response is very encouraging..working on an article on triads next.

14. ### tejas..........

Very good thread. Good Job Dennis.

15. ### LiquidNew Member

ok maybe this is covered...and maybe this is a dumb question...but im a little confused....about the difference between a minor and a flat... A minor is half step below A major....and Ab is also half step below....wait is that correct?

ok so i guess the question is...whats the difference in flats and minors?...

and how would u form the C minor chord :S

16. ### dennisThe Bhangra King

liquid, u are confused!! ..but dont worry.
A triad consists of 3 notes.
Minor applies to a triad whereas flat applies to a single note.
In Aminor we have the major 3rd being lowered a half step. The other 2 notes remain the same. Hence we are "flatting" only one of the 3 notes.
i hope that clears it up a little.

17. ### LiquidNew Member

yea that does...thanks ..

so whats the difference between an Ab chord and an A minor....they arent the same....so whats the "official" explanation behind this...

18. ### dennisThe Bhangra King

A minor has the notes: A C E

But for Ab major:
The Ab scale is:
Ab Bb C Db Eb F Gb
Hence Ab major would be : Ab C Eb

19. ### LiquidNew Member

ok that makes sense and all..

but now i have another question...( lol dont worry its less complex)..

why do u guys write Ab major....why not just Ab....i mean isnt it understood that it is a major chord?..

and is there such a thing as Ab minor?...and how would u form the scale for this.....ud form the Ab scale...then just take every major interval and make it into a minor by lowering it a half step?...sound good?

20. ### dennisThe Bhangra King

1.yes , it is

2. Obviously there is a Ab minor. U are correct except that we will only lower the major 3rd to get the triad.
Ab : Ab C Eb
Ab(minor): Ab Cb Eb
Notice only the major 3rd C is lowered by a half-step to get Cb.
clear??