If you've always played guitar in an E standard tuning then you know that the lowest note you can possibly play in that tuning is the low E on your 6th string.
As a result, the lowest sounding chord on guitar in standard tuning is the open E chord.
It's for this reason that so many songs are written in the key of E. Because E has a full bodied, "meaty" sound that resonates in the listener's ear. The E chord has balls!
Play any chord that is sonically above an E chord and you hear the "meat" diminishing, it somehow loses its punch.
That's not to imply that songs written in other keys can't be great songs, it's only to say that there's a special "bottom end" flavor in E that you can't always get in other keys.
Unless, of course, your lowest note on the guitar is not, in fact, an E.
Which brings us to today's topic, drop D tuning.
Drop D tuning has been around as long as the guitar has, and is a very popular tuning method, especially in country, folk, southern rock, and more recently, even in grunge.
Tuning your guitar to drop D is easy. You simply lower the 6th string, your low E string, to a D.
In the absence of a digital tuner you can just play your open 4th string (D), at the same time as you play your 6th string, and lower the 6th string until it matches the tone of the 4th string. When in proper drop D tuning, the 4th and 6th strings will be "octaves" of each other.
Now that you are in drop D tuning, play a standard open D chord, but now play it using all 6 strings. The 6th string now becomes the "root" note of the chord.
Notice the difference? All of a sudden your D chord has all the "meat" and punch that the E chord did previously. Even more so now that it is lower than an E.
You might say that the D chord now has a "swampy" kind of feel.
What can you do with this drop D tuning? First of all, experiment. Second of all, come up with some new stuff, play around and have fun with it!
You will have to make some fingering adjustments when playing other chords in drop D.
For example, when playing a G chord in drop D, your root or bass note (G), will now be located on the 5th fret of the 6th string instead of the 3rd.
Many players will play a G chord (in drop D) by playing the note on the 5th fret of the 6th string (G), and barring the notes on the 3rd fret of the 1st and 2nd strings (G and D respectively).
This produces a G chord that also has that "swampy" feel to it.
Another variation on drop D tuning that you can do is to lower the 1st string to a D as well.
This, of course, presents some new challenges for chord fingerings, but it also opens up some new doors sonically.
It's funny how one small change on the guitar - whether it's dropping to a D, or discovering a new chord, or strapping on a capo - can light a spark of creativity when it feels like you've been swimming in a sea of "sameness".
So if your guitar playing is feeling stagnant, like you are re-hashing the same old thing over and over (and we've all been there), try mixing it up - by dropping it down....to a D!