Bob wrote:
Drop tuning is tuning one or more guitar strings lower than "normal".

From: Wikipidea
http://en.wikipedia.org/wiki/Suite:_Judy_Blue_Eyes

"Suite: Judy Blue Eyes" is a song — or rather, a suite of short
songs or sections — written by Stephen Stills and performed by
Crosby, Stills and Nash, which first appeared on their self-titled
debut album in 1969. It was also released as a single(edited and
in mono), going to #21 on the Billboard Pop Singles chart. The
song is ranked #418 on Rolling Stone's list of the 500 Greatest
Songs of All Time.

The group has performed this song many times, most famously at
the Woodstock and Live Aid festivals. The title is presumably a
play on words for "Sweet Judy Blue Eyes."

The acoustic guitar for the song is tuned to a very unusual tuning.
Rather than the strings being tuned to the traditional EADGBE,
they are instead tuned to EEEEBE. Stills used this same tuning for
"4+20". He uses a similiar tuning for "Carry On" but drops the
notes down one half step. (EbEbEbEbBbEb)

Jeff

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