Watch the Lesson 9 online guitar lesson by David Hamburger from Fingerstyle Blues Handbook 2

Dropped D tuning (DADGBE) and open D tuning (DADF#AD) have the same bottom three notes, so it can be tricky trying to figure out which one someone's using when you're listening to a recording. Here's a hint: if they're in dropped D, the top three notes of their D, G and A chords will still sound the same as they would in standard tuning. If you don't hear all the usual notes on top, they're probably in open D tuning.