All About Intervals

April 1st, 2008 Print Tip E-mail Tip

Well, not quite all about intervals, but at least some info.

There are two types of intervals: melodic intervals and harmonic intervals. A melodic interval refers to the degree of pitch separation (highness or lowness) between two consecutively-sounded notes, while an harmonic interval refers to two simultaneously-sounded notes. We're going to focus more on melodic intervals here.

When you play the opening two vocal notes of "Over The Rainbow" (Some - where), you are playing a melodic interval. An interval can be ascending, descending, or remain stationary (the static interval of a unison). I've found the easiest way to visualize melodic intervals is in a linear fashion along a single string. Let's use the 2nd string (B) and start with our lowest-sounding pitch being the C note at the 1st fret on the B-string.

This chart will give you the details:

(The slash notes are enharmonic equivalent notes—identical pitch, but different note names)

When computing a melodic interval, always use the lower-pitched note of the pair as your reference note or starting point. For example, if you wanted to play a descending perfect 5th interval from the C-note at the 8th fret / 1st string, you might at first think to play a G-note at the 3rd fret / 1st string, since ascending from C to G is, in fact, a perfect 5th interval—but, when you use the lower note (G) as your reference point, the higher note (C) is, of course, a perfect 4th interval. If you look at the Intervals Chart, you'll notice that a perfect 5th interval has a separation on the fretboard of 7 frets. So if you count down 7 frets from C (at 8th fret / 1st string) you'll end up at the correct note of F (1st fret / 1st string).

So use the lower note as the reference point and count the number of frets down to it (for descending interval calculation), or count the number of frets up away from it (for ascending interval calculation).

Of course, in real life, you won't always be playing linearly along a single string. Visual fretboard patterns will become evident and memorized for intervals (whether melodic or harmonic) that span a given number of strings.

Ear training by the use and repetition of intervals is simplified when you just use a single string, because the fret-to-fret intervals are easily calculated, and there are minimal timbre or tonal differences when you remain on just the one string.