First off, you will need to re-tune your guitar to what will probably be the strangest tuning you have ever used. Guitarist John Rzeznik favors these types of tunings for his acoustic work.
The tuning he uses for "Iris" requires you to tune your 6th string down to a B. Then all of the other strings are tuned to a D. So the complete tuning is: B D D D D D
This creates a sound almost like 2 twelve string guitars playing together. The lower B string is usually just used for the moving bass lines. All in all it creates a nice full sounding and unique sound.
Your guitar may not like such a drastic tuning change though. Mine certainly didn't which I complain about a bit in the video lesson. 🙂
Your guitar may require a little intonation adjustment for you to make everything sound in tune all over the fretboard.
In any case, this Iris guitar lesson video will teach you the whole song in it's entirety. It really is quite a beautiful song that is made very easy to play due to the unique tuning.
If anyone out there is hoping to play "Iris" for their significant other, I am sorry that I can't help you with the vocals. I am the last person on earth you would want to take a singing lesson from. Haha!!
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