Overall Rating: 4.1 (of 5)
<Playing over songs when all you have to work with is some major, modal, or pentatonic scale, can be quite a challenge, especially if your goal is to create a meaningful solo. Anyone can memorize a group of notes and run them up and down over the changes. While this may indeed produce some satisfying results, somewhere along the line it will break down, usually sooner than later.
The key to making the changes happen is targeting notes from the scale you are using that coincide with the same notes in the chords being played. One way to begin this process is by setting the lines of tones to be targeted.
For example: you and a friend are playing the groove D A G D (4 beats each). You can blast away on the D Major scale and hope to get lucky or have a set line from which to shape your scalular ideas. Each chord is made up of three notes from the scale (basic major and minor triads, in this case, MAJOR only) so there are three points to start from in the first chord (D). This chord is made up of D, F#, A.
Making a list of chord tones in each chord is very helpful. G=G,B,D and A=A,C#,E. Also if you know the musical alphabet:
(A - Ab/G# - G - Gb/F# - F - E - Eb/D# - D - Db/C# - C - B - Bb/A# - A)
which is a series of twelve repeating notes (5 have two names but sound the same), it makes it a whole lot easier to navigate.
So, let's start with the note D in the D chord. The closest note in the A chord to D is C#. Our line is now D to C#. The closest voice in the G chord is back up to D, but let's continue moving downward in the alphabet to B. Our line is now D to C# to B. The last chord is D again and if we continue moving downward it brings us to A.
Note that all the choices come from the chord tones themselves. The final line is D to C# to B to A (1 note for each chord that passes).
While it is important to have a firm intellectual grasp on this concept, it is really easy to SEE on the guitar. Here is how it sounds: