What? ... Modal Who?
Open tunings are called such, because when you strum the guitar in it's "open" position -- meaning no chords being fingered with the left hand -- you have a ready-made chord. That is to say, if you strum all six strings, by themselves, you'll hear a chord. If you produce a G chord, you've got an "Open G Tuning." If you produce a Bm chord, you've got an "Open Bm Tuning," and so on. There's not really anything "easier" about using an open tuning, as compared to any of the others ... however, an open tuning can give you a bit more freedom to do some things that the other tunings just won't allow.
Aside from the standard E.A.D.G.B.E tuning for guitar, there are other ways of twistin' up them strings and really having some fun! "Dropped" tunings ... "Modal" tunings ... "Open" tunings ... and "Transposed" tunings have been around since the dawn of time -- you'll find the details of each in the tutorial, titled I Gotcher Modal Tunings ... Right Here. Basically, these tuning styles create a different sound for the guitar ... most notably, a droning effect -- due to certain strings/notes ringing through chord changes and creating chordal modifications that would never occur using a standard tuning. Once you familiarize yourself with one of these tunings, all the others become something like "variations of the same theme."
Although this site explores many tunings, and I tend to favor less than 6, there is one very special tuning that has stuck with me like glue ... so much so, that I'm bold enough to call it:
The open G tuning I use is quite unique and a whole lot of fun! It's been around for ages, but I discovered it on my own without knowing that, so I consider it "mine." Plus, there's a simple little twist I put on it by simply tuning the #6 string up to a G instead of down to the usual D -- and that "simple little twist" makes a pretty big difference in the sound of it ... and in the resulting playing style, as well!
The #6 and #5 strings, being tuned to the same note, have the tendency to phase in and out of frequencies with each other - creating a really big bottom-end, in the process. The perfect example of this, can be heard in the first four measures of Naked Moon
As is readily obvious, the six strings may be divided into two sections: The first section, the #6 and #5 strings, acts as a droning bass and percussion effect ... while the second section, the #4, #3, #2, and #1 strings, presents the usual chording and rhythm guitar effect. This style of playing presents a nice full rhythm and percussion sound to the guitar that would be impossible to achieve with only one guitar and a standard tuning. At times, it sounds as if two guitars are playing ... and indeed, two guitar parts are being presented.
Another thing I like about an Open G Tuning, is the fact that you can pretty much use all the same chord fingerings that you know from the standard tuning. So, if you are already familiar with the standard guitar tuning, the open G tuning will be very easy for you to adapt to ... and if you are learning to play for the first time, you won't be entirely lost when you decide to use a standard tuning, either. Cool? I think so!
General Rule of Thumb:
Don't use any finger positions on the #6, #5, and #1 strings (the ones that were changed from the standard tuning) - keep those "open" ... and finger positions from the standard tuning will work:
For example, see above: The C chord from the Standard Tuning, sits in the same place on the Open G Tuning ... but one position (#5 string) is not fretted ... you play all six strings, and wind up hearing a C9 chord, with a G bass.
It's quite adaptable to/from the standard guitar tuning. Also, understand, right- and left-hand techniques are the same no matter which tuning you use, but each tuning presents it's own distinct and very exciting language ... it's own individual personality ... it's own unique "mood" - and is unlike any other.
If you want to experiment, head on over to I Gotcher Modal Tunings ... Right Here and see what happens!
Alan's String Guages Chart
If you want to create a custom string set to match an alternate tuning, check out my handy (hard-to-find) chart!
And, finally, here are some cool books for you to check out:
The Complete Book of Alternate Tunings by Mark Hanson
Reveals Hanson's more elaborate, and very commendable, effort on the subject ...
The Alternate Tunings Guide for Guitar by Mark Hanson
Hanson's "quickie" on the subject. If you want something basic, here's a good book for a great price.
Alternate Tunings Picture Chords by Mark Hanson
Beginning Slide Guitar by Mark Hanson
If you want to learn the basics of playing "Slide" guitar, or "Bottlenecking," this one will take care of you ... and at the right price, too!