Seleting a Scale to Jam With

[Tim]

I am trying to improve my ear and the ability to jam along with CDs and other backing tracks. I always seem to come across a small problem when attempting this endeavor.

I start the song and hit and pick several notes on the sixth and fifth strings. I can figure out what key the song is in. Then 60% of the time, (well sort of) I can play along with the song. A lot of times I cannot tell if the song should utilize a minor pentatonic, major pentatonic or a major scale. How does one tell which scale to use over songs?

Example, I pick a favorite instrumental song. I start playing the song in the CD player. I pick notes on the 5th and 6th stings until I find that the song is in the key of “A”. So then I try the A minor pentatonic. It does not sound right. So I try the A major pentatonic. It does not sound right. So now I try the A major scale. It sounds good except on one or two notes. I am now at the point where I am saying to myself that maybe it is an A 7th scale or maybe a diminished scale.

Can any Fretters tell me if I am pursuing this the correct way? If I can figure this out I will be accomplishing a major milestone in my playing. Thanks for any help provided.

[Katastrophe]

The vast majority of rock music (and a lot of blues, too) is going to be in a minor key. So, when someone says their jamming on a blues in "A," try A minor pentatonic.

EDIT: Also, don't forget that some guitar players tune 1/2 step down, and you may have to adjust accordingly.

[jpfeifer]

Hi Tim,

The most important part of determining which scale to play over a song is to understand the chord progression being played. Once you have the chords then you can start to determine what kinds of scales will work over them.

If the song is based over chords derived from a major scale then you can play major pentatonics over the progression and it will sound good. But if the song is built from chords derived from a minor scale then the minor pentatonics or blues scale should fit.

There are variations on this too. Some songs don't stay in the same "key center" for the entire tune and this requires that you adjust your scales to different keys through the progression of chords. This is most common in Jazz but you also find this in other kinds of music. For example the song "Little Wing" doesn't stay in the same key center for the whole tune. It drives me crazy when I hear someone jam on one blues scale for that whole tune because it doesn't fit at a certain part of the chord progression.

The best way to get familiar with this concept would be to get a book on music theory as Robert had suggested in a different thread. There is also some great information on the web that explains some of these concepts.
Look for topics in the following areas: "Harmonizing the Major scale" This will explain how the major scale is used to create a series of chords that you can use to write songs. In this same way, if you understand this series of chords you can more easily determine when to use the major scale, and what key to play it by analyzing the chord progression of a song. In a similar way, you can look up information on "Harmonizing the Minor Scale" to become familiar with the common chord progressions used in minor keys.

I know this is a lot of information. I hope this helps,

-- Jim