Intervals: The Major 7th

So, as promised, this week we’re going to look at the major 7th. As I explained last week, in this article, the 7th can be quite a complex interval because of the two part definition that all out intervals need (one based on letter names, the other on actual distance on the fretboard).

To recap, here is the first half of our definition of a seventh:

A 7th is an interval that covers the distance of 7 letters

…which means that you count the letters with the first letter as one. For example:


1 2 3 4 5 6 7
A B C D E F G

“A” to “G” is a 7th, and any note with an “A” as the letter (A flat, A sharp, plain old A natural…) to any note with a “G” as the letter (same deal: G flat, G sharp, G natural, G double sharp…) counts as a 7th because there are 7 letters.

The Major 7th

The second part of the definition has to do with the distance on the fretboard, and it tells us whether the 7th is major or minor (or diminished or augmented…technically). The major 7th, which we’re going to look at today is 11 frets distance (along one string- equal to 11 semitones). Just slightly less than the octave (which is 12 frets- from A to A, or G to G…).

So here is the full definition of a major 7th:

The Major 7th is an interval that covers the distance of 7 letters and 11 semitones

The way it works is that both parts of the definition have to be fulfilled for it to count as a major 7th. So, for example: G on the third fret E string, to the F# on the 14th fret on the E string. If we called that F# a “G flat”, it wouldn’t be a 7th because that now spans 8 letters, but also, if, instead of an F#, we had just an “F”, it wouldn’t be a distance of 11 frets, and so wouldn’t be “major”.

So here is the tab for a major 7th:


e--------
B--------
G--4-----
D--------
A--3-----
E--------

So this is another example: the C on the third fret of the A string, and the B on the 4th fret of the G string. This shape can obviously be moved to wherever you need to if you want to work out where the major 7th is (also check out major 7 chords for chord shapes using the major 7th).

Soloing

The major 7th is only one fret lower than the octave, which means that in a scale it’s only one fret away from the root note. This means you’re going to have to be careful where you use it! As I mentioned earlier (in a previous post) the 7th is usually considered an addition to a chord- except in Jazz- so therefore you expect the major 7th to sound bright and majory, but also very Jazz (and if it doesn’t make sense when I describe it with words, how about you just play it instead?).

The major 7th is an “extra”, and you should treat is as such- don’t use it too often, but just enough on the right occasions can add life to a solo. Just like salt on your food- it doesn’t come with the food (usually added as an extra seasoning), and if you use too much salt the food becomes inedible, but just enough at the right times (you wouldn’t put it on ice cream, for example, would you?), can add life and flavour to your food.

So there you go- the major 7th is like the seasoning on the food of soloing…or something…
Rob.

August 26, 2011 at 4:00 pm | Music Theory | No comments