“Wish You Were Here” by Pink Floyd is a great example of using the pentatonic scale pattern on the guitar with added chord tones as a result of pedal tones. It’s also a good introduction to lead guitar playing.
The song mainly features acoustic guitar playing. It opens with a 12-string guitar playing a combination of chords and melody in the open position. This track becomes the underlying accompaniment for a second acoustic guitar (a standard 6-string) that plays in a more lead-like fashion.
When you’re first practicing the 12-string opening to this song, ignore the chords you hear and focus on just the scale melody (which you can play on a regular 6-string guitar). The scale melody starts with a hammer-on from the open 5th string, A, to the 2nd fret of the 5th string, B.
These notes and the ones that follow them are all drawn directly from the open position G major pentatonic scale pattern shown here.
Note: This scale pattern can be either G major or E minor pentatonic, depending on which note functions as the tonic. It’s played over both the chords G and Em in “Wish You Were Here,” so you can think of it in either its major or minor form. To keep things simple, here it is called a G major pentatonic; the opening resolves on a G chord, anyway.
If you’re new to using scales to play melodies, this is a great song to start with. The tempo is nice and slow, you only need a finger or two, you don’t need any alternate picking, and the hammer-on articulation is a cinch.
Looking at the chords, the progression is based on Em, G, and A7. But instead of playing standard shapes, the guitar holds and sustains the 3rd fret of the 1st and 2nd strings. This use of pedal tones ends up creating chords with more depth and color. It also gives them more complicated names, as you see here. (The numbers indicate fingerings.)
Em7: The Em7 chord is a partial shape based on a common open Em chord. The addition of the D note at the 3rd fret of the 2nd string makes the chord Em7.
G: The G is a standard open G. You can play an open G chord by using either the open 2nd string, B, or the 3rd fret of the 2nd string, D. Both notes are part of the G triad, G-B-D. By using the D on the 2nd string, you keep the same notes, D and G, sustaining over all three chords, creating a type of pedal tone.
A7sus4: Keeping the 3rd frets of the 1st and 2nd strings as part of the A chord adds a 7th and 4th and removes the 3rd, hence the name 7sus4. The open 3rd string, G, is another 7th.
The second guitar that comes in playing lead licks also uses the G major pentatonic scale. It begins by sliding along the 3rd string from the open position pattern to the next position between the 3rd and 5th frets. From there, it uses some standard guitar articulations, including slides, pull-offs, hammer-ons, bends, and double-stops.
Note: Bending on an acoustic guitar is difficult, especially in this position. To play this part properly, use very light-gauge strings with an unwound 3rd string, G, or use an electric guitar.