im aware of the blues scale, which is a minor pentatonic scale with a flattened 5th included (correct me if im wrong).

can this scale be used (e.g. in a lead guitar part, or an improv bass part) in a song with a major key?

also ive read that when someone uses a minor 3rd while playing/soloing over a major chord, it sounds quite 'bluesy'. can anyone elaborate on the 'bluesy' use of minor 3rds?

many thanks.
i need to get a better signature.
Yes, you can use it over a major chord or key. The tones in the blues scale when played over a major chord outline the "Jimi Hendrix" chord, the _7#9, which to most people's ear sounds very bluesy. Now, if you stuck that chord in just anywhere it probably wouldn't fit. But simply, yes, you can play the blues scale over a major chord.

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