Scale and Chord relationships

[thibaj]

Hello. I have a question regarding the chords that can accompany typical scale types. For instance, the major scale can be used when playing with any of the seven chords based on the diatonic scale notes. However, when shifting to a different scale, such as a pentatonic, from a music theory perspective, which chords match-up to that scale? Thanks.

[cyberfret]

Here are a couple of ideas about how pentatonic scales are used.

A chord progression will be either major sounding, or minor sounding. There are modes and different kinds of scales, but just break them into 2 different categories at first.

Play a major pentatonic scale over a major type progression
Play a minor pentatonic scale over a minor type progression

When trying to figure out whether a progression is major or minor, try to decide which chord is home base. Maybe the first or last chord of the progression, but where you feel sounds like home. If it is a major chord then you have a major type progression, if it is a minor chord then you have a minor type progression.


Last, you can play a minor pentatonic over a major type progression...if the song has a blues feel, or you can superimpose a blues feel over the song. For example the chord progression (G, Em, C, D) is a major type progression, and therefore uses a G major pentatonic scale. You can also use a G minor pentatonic if it sounds right to you (blues feel). If the same set of chord were in a ska tune, the minor pentatonic might sound awful.

Note: you can not use a major pentatonic over a minor progression, It will just sound wrong.

This is an over simplification but should give you some ideas.

You can also use different pentatonic scales for individual chords, Use a minor pentatonic scale for a minor chord and a major pentatonic for a major chord.

example:
Chord progression G Em C D G

Use G major pentatonic over the whole chord progression
Use G minor pentatonic over the whole chord progression....If it has a blues feel to it.
Use E minor pentatonic over the Em chord (the same notes as G major pentatonic)
Use a C major pentatonic over the C chord
Use a D major pentatonic over the D chord


--Shawn