### Wednesday, October 11, 2006

## Lesson - 52 : Refresh Knowledge on Intervals

Let us recall and reinforce some of our earlier understandings on Intervals.

Intervals measure the distance between two notes and also the name given to them indicates the quality of interval.

We saw that Major Scale has the Perfect Intervals for 4th and 5th and all other intervals w.r.t. Tonic are Major intervals.

In case of Harmonic Minor Scale, the 3rd and 6th intervals are Minor and all other intervals are same as Major scale.

Then we also learnt the method of finding the intervals of any note to a note above it, this was measuring the number of semitones they were separated and based on the table we can name the intervals.

The reference table is reproduced below again :

In order to get any interval between any two notes, based on the difference of how many Semitones they are separated the following table can be used :

Alternative way to calculate any interval is,

- assume the Major scale on the base note and

- measure the relative distance of the Major scale interval and

- adjust for the variations to get the final correct intervals.

For example, if we have to find the intervals between F and B, remember the scale of F major,

and we know in F-Major we get B-flat as the fourth note to give the Perfect 4th interval.

But in our case, we need the interval of B which is a semitone higher.

So the interval has to be Augmented 4th.

(To check it, if you measure the actual semitones separation based on the Keyboard visualization, this comes to 6 semitone; as per the above table, this is called the Augmented 4th since F and B is separated by 4 letters alphabetically, it cannot be 5th.)

So have some practice on that.

Aim is that even if we could not tell mentally, check leisurely using the keyboard figure and verify from the table and confirm yourself.

With time passing, you can do that mentally and quickly also.

Our aim is to understand the concept and not writing some exams now..!

So donâ€™t worry about any complexity initially. In fact everything is simple mathematics of addition or subtraction !

Certain other basic formulae you shall remember are :

In nut shell, the path of semitone wise progress is

In our next session we will see a new Concept "Inversion" of intervals.

**(****Please Refer to Lesson 22****) (and other previous related lessons as you required!)**Intervals measure the distance between two notes and also the name given to them indicates the quality of interval.

We saw that Major Scale has the Perfect Intervals for 4th and 5th and all other intervals w.r.t. Tonic are Major intervals.

In case of Harmonic Minor Scale, the 3rd and 6th intervals are Minor and all other intervals are same as Major scale.

Then we also learnt the method of finding the intervals of any note to a note above it, this was measuring the number of semitones they were separated and based on the table we can name the intervals.

The reference table is reproduced below again :

In order to get any interval between any two notes, based on the difference of how many Semitones they are separated the following table can be used :

*(bracketed names are theoretical possibilities only, though sometimes may not have direct relevance in case of WCM)*

Alternative way to calculate any interval is,

- assume the Major scale on the base note and

- measure the relative distance of the Major scale interval and

- adjust for the variations to get the final correct intervals.

For example, if we have to find the intervals between F and B, remember the scale of F major,

and we know in F-Major we get B-flat as the fourth note to give the Perfect 4th interval.

But in our case, we need the interval of B which is a semitone higher.

So the interval has to be Augmented 4th.

(To check it, if you measure the actual semitones separation based on the Keyboard visualization, this comes to 6 semitone; as per the above table, this is called the Augmented 4th since F and B is separated by 4 letters alphabetically, it cannot be 5th.)

**So interval measurement ability is one pre-requisite skill while naming the chords etc.**So have some practice on that.

Aim is that even if we could not tell mentally, check leisurely using the keyboard figure and verify from the table and confirm yourself.

With time passing, you can do that mentally and quickly also.

Our aim is to understand the concept and not writing some exams now..!

So donâ€™t worry about any complexity initially. In fact everything is simple mathematics of addition or subtraction !

Certain other basic formulae you shall remember are :

In nut shell, the path of semitone wise progress is

**(Diminished---Minor---Major---Augmented)**or**(Diminished---Perfect---Augmented)**In our next session we will see a new Concept "Inversion" of intervals.