Ttyjfyk

In the wikipedia article for the song Iris it says there is an:

unusual guitar tuning in which most of the strings are tuned to D,
lending the guitar a chorus-like effect.

In a follow up article follow up article it says:

Perhaps the most famous example of this is the B-D-D-D-D-D tuning of
his signature hit "Iris"

Can somebody explain this to me? If one were to make every string of a guitar play D, wouldn't she have to completely re-learn how to play the instrument?

I have never played guitar so I do not know what "tuning" such as this is, but, to use another example, if every Piano player tuned her piano a different way, it would be impossible to play on any normal Piano.

Can somebody briefly explain how "tuning" a guitar works and why the B-D-D-D... tuning is different?

I do not know what "tuning" such as this as

A tuning defines the notes of the open strings on a guitar. Standard tuning is E-A-D-G-B-E but other tunings are rather common as well. The main reason behind this is the use of open strings, simplification for specific chord shapes and easier fingering for certain phrases that are important to the song.

One obvious example if playing with a slide. A slide typically touches all strings at the same fret, and so you want this to make a chord by itself. Popular turnings for this are "open E" (E-B-E-G#-B-E) or "open G" (G-B-D G-B-D).

John Mayer uses a lot of non-standard tunings. For example "Atmosphere" "Something's missing" and "wherever I go" are played in "E-B-E-F#-B-E" and he uses the second between E and F# as an interesting tension in his open chords. "Neon" he plays in "C-B-E-G-B-E" so he can fret the bass line with his thumb at a reasonable position.

If ... wouldn't she have to completely re-learn how to play the
instrument?

Yes. You have to relearn chord shapes and specifically scales. Improvising in a different tuning takes a fair bit of practice. On the other hand, it allows you to play things that would be very difficult or impossible to play in standard tuning.

Maybe it makes it more difficult to play for someone who's used to standard tuning, as all chord shapes are different. However, using just one shape, it's possible to move it up and down to produce the chords used in the song.

The idea is that the D notes will be very slightly 'out of tune' with each other, which produces what's known as the chorus effect, a sort of shimmering, not horribly out of tune. Somewhat like the sound of a 12 string guitar.

Any tuning is possible with a guitar, and, yes, all the chord shapes will alter. This makes it more difficult - there's another set of shapes to remember - but for lots, that's not a problem - some find tuning differently makes some chords easier to finger.

If one were to make every string of a guitar play D, wouldn't she have to completely re-learn how to play the instrument?

You do have to play the instrument differently, but it's not as bad as having to "completely re-learn" it. Many of the skills involved in playing an instrument (such as having an idea of what sound you are trying to get out of the instrument in the first place, and knowing any applicable theory) are fairly independent of the tuning of the instrument.

Even many of the physical skills (such as how to fret the notes, and all the right hand skills) are the same. Of course you do have to re-learn chord and scale shapes somewhat, but even that only applies to the intervals moving across the strings - the intervals moving up and down the strings stay the same, of course.

The advantage of using alternative tunings is that it makes certain note patterns and combinations physically easier than they are in standard tuning (and in above cases makes things possible that would be impossible in standard tuning). If using an alternate tuning doesn't make a part easier to play (including aspects such as being able to do appropriate articulations to make the part sound good), then you would probably use standard tuning...

All the answers tell you that you have to relearn chord shapes and structures which is true. I don't have much experience on guitar but once you have th basic skills like fretting, picking, speed and vibrato; it shouldn't be too tough especially since they are used mostly for a specific part ina song to make unique chord structures or sounds that are too tough with the regular tuning.
On piano if you want to play everything a note up the patterns change but intervals remain the same, atleast tonally. It takes some time to learn the first alternate tuning but after two or three tunings it will feel like second nature to you.

The mentioned B-D-D-D-D-D tuning is probably a gimmick that is only used for particular parts in specific songs. And yes, with a tuning like this, you'd have to relearn everything, and can't play most of what you'd expect a guitarist to play.

The guitar standard tuning is E2-A2-D3-G3-B3-E4. Within certain limits, you can tune each string up or down - two half-steps usually work fine; for a wider range you should change the string to a thicker or thinner gauge.

There are some popular alternate tunings that require relatively few adjustments to your playing:

• you can tune the whole instrument one or two half-steps down to get a deeper, fatter sound. You then have the choice of playing the piece on the same frets, and it just comes out transposed, or you shift everything up one or two frets to keep the original pitch. As long as you don't use open strings, that's easy.


• you can tune the lowest string down two half-steps ("Drop-D"), which expands your range for a fatter sound, and allows you to play power chords on the lower three strings very easily. You can play melodies and chords on the five highest strings just as you're used to.


• you can combine the two: drop everything two steps, and the lowest string by an additional two, to get "Drop-C".

Anything that goes beyond these alternate tunings is, IMO, quite exotic and not something you'd expect a regular guitar player to handle.