Originally Posted by: equatorParallel Scales, is when you use the same fingering to play to different keys:


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If you play this scale on fret 8 You get "C minor" and the notes you use are: (C-D-D#-F-G-A#)

Use the same fingering on fret 5 and you get the notes of the "C Major Scale
with the tonic shifted to "A" or the "A minor scale".
so you play two different scales using the same fingering:
That fingering allows you to play: "C minor" and "C Major" in two different positions.
Take a look to the notes.
C minor:{C-D-D#-F-G-A#}
C Major:{C-D-E-F-G-A}
So, if you are playing a song in the key of "C Major", and you use the parallel scale: your soloing is gonna be a disaster, becouse then you will be playing
(D#-A#) wich are not part of the "C Major Scale".
And the parallel scale don't have the "E" note that makes the
"C Major chord" (C-E-G)

On the other hand, Relatives Scales have the same notes:
C Major: {C-D-E-F-G-A-B}
A minor: {A-B-C-D-E-F-G}
Both scales contein the notes you need to make the "C Major Chord"

Bottom line. When you play a Blues solo over a major chord, use relative scales.
A minor Blues Scale: {A-C-D-Eb-E-G}
Relative major:....... {C-D-Eb-E-G-A}
Here you can see that both scales have the notes used to make the
"C Major Triad"

I Quote here what the INCREDIBLE SCALE FINDER book has to say about the blues scale:
..."The blues scale is a slight variation on the minor pentatonic. This six-note scale contains all the notes in the minor pentatonic scale plus the dininished-5th interval"
That is why I said the blues scale is not pentatonic, wich means five notes.
The Blues Scale is rather a Hexatonic scale, becouse it has six notes.
That added note is known as the "Blue Note" and was placed there to form a chromatic tone.
If you play the parallel scale not only you play the wrong notes, but you are missing the essence of Blues(the chromatic tone), and you dont have the note that defines the quality of major chord, the major third.

I know all of this. It will NOT sound like crap if you play the pentatonic or blues minor scales. By the way, the only disastrous thing here is how this theory has been phrased. The Cminor scale does not contain a D#, it contains an Eb. While those are sonically the same, the names have a meaning. There is also no A# in Cminor. However, there is a Bb. However, you would not play a natural minor scale over this backing. If you play a Relative scale, it WILL NOT SOUND GOOD, even though it contains the same notes, because you will stress weak notes. If you DO stress the strong notes, you're not PLAYING a parallel scale your playing the original major. Do NOT play a relative scale in this situation. I know what I'm talking about and have heard people try to do it before. It sounds like ass.