I have been working on Amazing Grace with the drop D tuning. This may be a silly question, but will switching back and forth between E and D dammage or shorten the life of the string? I have not tried to tune my guitar to anything other than EADGBE before and when tuning down it seems I am really undoing the string.
Welcome to the musical madhouse.
Changing tuning might have some slight effect on string life. But I haven't found that tuning down makes any appreciable difference. There are some tunings where one tunes sharp -- that would, I imagine, be more likely to affect the life of the strings.
But I think drop D tuning and double drop D are perfectly safe and riskfree tunings. If you're playing an electric guitar with a floating bridge, you may have trouble with intonation if you change the tuning. A fixed bridge would be better. If you're playing it on acoustic, don't worry about it.
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