Study Intervals and Correctly Identify Them

At http://www.foriero.com you'll find a free download and a video to watch regarding music intervals. I used to be a monitor in the zone at the Hear and Play website. There were many moderators at that time and it was a huge community of musicians. I would read some of the online lessons by Jermaine Griggs
ans I took some pretty good notes from these. So, here goes a study on intervals. Thanks for reading and I hope this sincerely answers some of your questions on the subject.

Let’s study intervals and how to correctly identify them. Many times musical intervals are commonly mispronounced and misidentified.

For example, C# to F is not a major third, even though it creates the same sound as a major third. Yes, two notes played harmonically (together) can create the same sound as an interval you’re used to hearing, but depending on how you name them, they can be totally different intervals. C# to F is a fourth (generically) and a diminished fourth (specifically).

Second Intervals

Db / Eb
D is 1
E is 2

Gb / Ab
G is 1
A is 2

Gb / A#
G is 1
G is 2

B / C#
B is 1
C is 2

Third Intervals

C / E
C is 1
D is 2
E is 3

Db / F
D is 1
E is 2
F is 3

C# / E#
C is 1
D is 2
E is 3

E / G#
E is 1
F is 2
G is 3

Db / F#
D is 1
E is 2
F  is 3

O.k., so now you are becoming a pro at determining generic intervals.

For example, F to A is a third apart and G to C is a fourth apart. Db to F# is a third interval.

So now you have learned the fundamentals determining the name of an interval. Here’s a chart that might help in understanding intervals.

Number of letters counted  |  Generic interval name

1                                                                                           unison
2                                                                                         second
3                                                                                         third
4                                                                                        fourth
5                                                                                         fifth
6                                                                                         sixth
7                                                                                          seventh
8                                                                                         octave (eighth)

Now with generic intervals, we’re not concerned with sharps, flats or key signatures. We’re just talking about the alphabet. With the generic name, we cannot fully build chord structures because it’s too broad.

For example, all of these intervals are thirds:

C to E
Cb to Eb
C# to E#
C to Eb
Cb to E
C to E#

So, you just can’t say third if you want someone to play a particular set of notes. While third is a way to determine what to name an interval, more specifically is needed to really know what to play exactly.

Specific intervals are names like “major thirds,” “major seconds,” “perfect fifths,” and others. The ‘titles’ you see in front of the intervals are what we call qualifying terms. They change generic intervals into specific ones, which tell you exactly which notes to play (unlike the long list of thirds).

Now counting specific intervals is a little different than counting generic intervals. Recall that generic interval counting simply involves the number of letters or notes it takes to create the interval. From C to E, we’d count C as 1, D as 2, and E as 3, which means that this is a third interval.

With specific intervals, we will be counting differently. Specific intervals tell us exactly what’s going on. They don’t undo the  “generic” techniques we learned --- they simply add to it.

It is impossible to have a generic second and then get a major third from the same interval. So, it is important that whatever you determine during “generic” naming holds true when you are using qualifying terms to create specific intervals.

There are different qualifying terms:

Perfect
Major
Minor
Diminished
Augmented

How do we know which one of these terms is suppose to go with our interval? It’s simple. We count half steps. If you’re new to music theory, a half step is also known as a semitone. It is pretty much the smallest interval. From key to key is a half step. C - C# is a half step. E to F is a half step. Notice I’m not skipping any notes. If you skip a note, you aren’t moving in half steps. You’d actually be moving in whole steps. In this case, we count half steps only.

Here’s a poem that will help you remember half steps vs. whole steps:

Half steps are from key to key
With no keys in between,

Whole steps always skip a key
With one key in between.

Now the counting does not start on the first note like it did with generic counting. We are counting the actual steps. So, how many half steps are in between C and E?

C to Db is 1, Db to D is 2,  D to Eb is 3 and Eb to E is 4. The answer: There are 5 half steps between F and Bb.

The chart below shows the interval names and the number of half steps associated with each type of interval.

Interval Name |  No. of half steps

Unison                 0
Minor second  1
Major second  2
Minor third       3
Major third       4
Perfect fourth  5
(Tritone)          (6)
perfect fifth      7
minor sixth        8
major sixth        9
minor seventh  10
major seventh  11
octave (eighth) 12

Notice from the chart above:

The terms “major” and “minor” are reserved for second, third, sixth and seventh intervals.

The term “perfect” is reserved for unison, fourth, fifth, and octave intervals, though you really don’t hear it a lot with unison and octave. So, fourths and fifths, for sure get the “perfect” term. You won’t ever hear perfect second or perfect third because the perfect term only goes with unison, fourth, fifth and octave, as I noted above.

Later, you’ll learn about augmented and diminished terms. They have purposes as well. So, here’s the tricky part. You now know that at interval with 4 half steps separating the notes is called a major third. An example of this would be C to E. This is the same interval that helps to create the major chord.

Let’s look at an interval like C to Eb. What would this be called? Just count up the half steps:

C to Db is 1
Db to D is 2
D to Eb is 3

3 half steps = minor third

Keep in mind that your answer must also pass the “generic interval” test. Is C to Eb a third?

C is 1
D is 2
E is 3

Yes, it passes. What about C to D#?

C to Db is 1
Db to D is 2
D to D# is 3

It has three half steps and these 3 half steps mean a third for sure but would this pass the generic test?

C is 1
D is 2

According to what we know about naming intervals, this should be a second. Any  C to any D is a second. This is where you’ll need to use the qualifying terms: Augmented and Diminished.

Augmented means to make bigger.
Diminished means to make smaller.

In this case, we have a second that is three half steps apart. Since we can’t call it a third, we will have to call it an augmented second… in other words, a “second made bigger.”

So basically, when an interval is a half step larger, it is said to be augmented. When an interval is a half step smaller, it is said to be diminished.

What is a major third up from D?

Step 1: Determine generic interval:

D is 1
E is 2
F is 3

So far, I know that a third up from D is going to be some kind of F. From our chart above, we know that major third intervals always have a 4 half steps in between the lower and upper note.

So start as D:

D to D# is 1
D# to E is 2
E to F is 3
F to _ is 4

This is the big question. Do we say F# or Gb? Well, since we’ve already done step 1 and we know we’re looking for some kind of F, it would make absolutely no sense to choose Gb. Therefore, the answer is F#. From D to F# is a major third interval.

1.     A perfect fifth up from B
(B up to F# is a perfect fifth)

Generic:
B is 1
C is 2
D is 3
E is 4
F is 5

Specific:
B to C is 1
C to C# is 2
C# to D is 3
D to D# is 4
D# to E is 5
E to F is 6
F to f# is 7

2.    A perfect fifth down from C
(C down to F is a perfect fifth)

Generic
C is 1
B is 2
A is 3
G is 4
F is 5

Note: Counting down generically is the same thing. Just count alphabet backwards.

3.    A minor third up from Eb
(Eb up to Gb is a minor third)

Generic
E is 1
F is 2
G is 3

Specific
Eb to E is 1
E to F is 2
F to Gb is 3

4.   A major sixth up from A
(A up to F# is a major sixth)

Generic
A is 1
B is 2
C is 3
D is 4
E is 5
F is 6

Specific
A to  A# is 1
A# to B is 2
B to C is 3
C to C# is 4
C# to D is 5
D to D# is 6
D# to E is 7
E to F is 8
F to F# is 9

5.    A major third down from G
(G down to Eb is a major third)

Generic:
G is 1
F is 2
E is 3

Specific:
G to F# is 1

F# to F is 2
F to E is 3
E to Eb is 4

6.    A perfect fourth up from F
(F up to Bb is perfect fourth)

Generic
F is 1
G is 2
A is 3
B is 4

Specific:
F to Gb is 1
Gb to G is 2
G to Ab is 3
Ab to A is 4
A to Bb is 5

7.    A major second down from C
(C down to Bb is a major second)

Generic:
C is 1
B is 2

Specific:
C to B is 1
B to Bb is 2

8.    A minor seventh up from A
(A up to G is a minor seventh)

Generic:
A is 1
B is 2
C is 3
D is 4
E is 5
F is 6
G is7

Specific:
A to A# is 1
A# to B is 2
B to C is 3
C to C# is 4
C# to D is 5
D to D# is 6
D# to E is 7
E to F is 8
F to F# is 9
F# to G is 10

9.    A major sixth down from D
(D down to F is a major sixth)

Generic:
D is 1
C is 2
B is 3
A is 4
G is 5
F is 6

Specific:
D to C# is 1
C# to C is 2
C to B is 3
B to A# is 4
A# to A is 5
A to G# is 6
G# to G is 7
G to F# is 8
F# to F is 9

10. A minor third down from F
(F down to D is a minor third)

Generic:
F is 1
E is 2
D is 3

Specific:
F to E is 1
E to Eb is 2
Eb to D is 3

Now you have a good understanding of intervals and will never quote a major or minor chord wrong again.

You may be interested in, Jazz Intensive Training Center

Best, "The beautiful thing about learning is that no one can take it away from you." B.B.King