What is a scale? / What is a chord?
This is one of the big questions which few people take the time to explain, or even to think through… Maybe it is because it seems to be so self evident, but it actually isn’t…
Think of a scale as a frame of reference…that’s all it really is. There are many conventions for scales (major, minor, various modes, symmetrical scales, etc.) but the bottom line is that they are mostly mechanical devices with which to string melodies inside. That’s really all they are. You may end up practicing many of them, and from a perspective of mechanical technique (i.e. how to best move your fingers…) they do have use.
Consider this, if a composer writes a tune based upon a particular scale and key, it would be to your advantage to be familiar with these ideas and perspectives…especially if you intend to create a solo or to improvise in some manner…
Chords are another strange problem for many beginners, in that most players learn some chords before they ever learn a scale. The fact is that chords are made out of scales… the simplest forms of chords (Diads and Triads, that is 2 note and 3 note chords) a usually directly based upon chords. For instance a C major triad is the 1, 3, and 5 of the scale (e.g. Do, Mi, Sol…). A ‘C’ major scale can create quite a few chords, such as C major, D minor 7, G dominant 7, and even a B 7 flat 5.
Another point is that a scale on the guitar is not a line of specific notes played in order in a specific part of the neck…that would only be a part of all of the notes in the Key of ‘C’ over the whole neck… My reason for mentioning this is that it implies that the simple scales you may run across are not the last word in scales, and as such, the basic chords you may be learning are certainly not the last word there either.
Melody / accompaniment
These two ideas relate to the mechanics of scales and chords, but not in as direct a manner as you might think. For instance melodies can be presented as chords, and accompaniment can be single lines of notes.
There is an irony in that scales have come from (at first) a consolidation of the tonality which many melodies might have. But now many composers use scales as a sort of prepackaged sets of harmonic implication… One creates the other.
As scales context for melodies, so then, harmonies created with chords can provide literal context and support for these same melodies. It might seem strange to think about melody…if, for instance, you are interested in such genres as death metal, but the idea still holds true.
