There are only a few more things to learn about intervals. If the distance is within a one octave range, it’s termed a simple interval . If it extends into the next octave, such as a 9th, 10th, 11th, or 13th, it’s called a compound interval . By the way, a math prime symbol (‘) is used to designate notes in an upper octave; for example, C to C’ to C’’.
If you ‘flip over’ and reverse the order of the notes in an interval, it becomes an inverted interval or complementary interval . Here’s a cool thing to know – when you invert an interval, the numbers always total nine and the sign (quality) is reversed. So, a major 3rd becomes a minor 6th (C to E and E to C); a minor 7th becomes a major 2nd (C to Bb and Bb to C); a perfect 5th becomes an augmented 4th (C to G and G to C), and so on.
How much algebra do you remember? Do you remember that performing the same operation on both sides of an equation doesn’t change anything and often simplifies finding the solution? The same principle applies to identifying intervals in music , especially in difficult or non-existent keys. Let’s say you’re familiar with the key of G, and you know that the interval of G to E is a major 6th. But, what about Gb to Eb, or Gbb to Ebb? As a guitar player, you probably don’t play in the key of Gb much, and there is no key of Gbb. Here’s an easy way to figure them out . . .
Transpose a difficult key or a ‘pretend’ key to a familiar one by lowering or raising both notes of the interval by the same amount. Gb to Eb raised by a half-step each becomes G to E – you know that one already! Likewise, Gbb to Ebb raised by two half-steps each becomes G to E – so, all of the intervals are the same. This is a great trick and you’ll use it more than you might think.
In fact, let’s try it right now and have some fun understanding intervals ! You’re right – it’s a test! In exercises 1 and 2, the task is to identify each interval – reviewing the chart before you start will probably be a good idea. Depending on your major scale knowledge, some of the answers are easy while others are much harder.
HINT: In staff notation, you can easily find the number (general name) by starting on the low note and counting the number of lines and spaces. The note you start on is number 1 . . . the note you end on is . . . whatever. That’s half the battle.
Exercise 3 will make you think a bit more, as you need to find the lower note which results in the specified interval. The correct answers for all of the exercises are provided at the end of the lesson.
Of course, understanding intervals specifically for guitar is the most important thing, so the following fret diagrams show the interval string patterns for 3rd’s, 4th’s, and 5th’s. You now know how to build intervals, so you can figure out the other countless combinations on your own. Root notes are light purple.
Well, that’s it for this lesson. Melody, harmony and improvisation all relate to understanding intervals , so make up your own exercises – just scribble down a few letter names and accidental combinations, and determine what the intervals are. You’ll be pleasantly surprised by how quickly you learn infinitely more about scales, chords, and the fret board. No kidding . . .
Answer key – from left to right
Exercise 1:1) aug 6 2) dim 5 3) mi 7 4) aug 5 5) mi 3 6) P 4 7) maj 7 8) aug 2
Exercise 2: 1) dbl dim 4 2) dbl aug 5 3) dim 3 4) dim 4 5) mi 6 6) dbl aug 4 7) dbl dim 6 8) aug 3
Exercise 3: 1) F# 2) A 3) D 4) F# 5) C 6) Bbb 7) Cb 8) Cx