RIFF 1: This solo is using the 1st Blues Scale in the key of A (starting from the 5th fret). When you listen to it you can hear the extra notes giving the solo a bluesy tone right away.
RIFF 2: This solo is using the 2nd Blues Scale in the key of A (starting from the 8th fret).
Put your practice to the test
Once you have practiced both the riffs, have a go at playing them along with the backing. This backing is suitable for both riffs.