I am currently learning the guitar, particularly solo-ing, and teaching myself by figuring out the Blues scale in various keys. At the moment I'm looking at the key of E.
The way I understand it (may be incorrect) the Blues scale is based on this formula:
1 b3 4 b5 5 b7
That should mean the Blues scale in key of E becomes:
E Gb A Bb B Db
However, in a lot of places, not the least being the very highly-rated Guitarist's Reference app on Android, the scale is said to be:
E G A Bb B D
Being a newbie I'm struggling to find the reasoning behind this, and how it applies to other keys. Any pointers would be greatly appreciated.