Hard Days Night Chord
So how was the chord played you ask? George Harrison was playing the following notes on his 12 string guitar: a2, a3, d3, d4, g3, g4, c4, and another c4; Paul McCartney played a d3 on his bass; producer George Martin was playing d3, f3, d5, g5, and e6 on the piano, while Lennon played a loud c5 on his six-string guitar.
Tagit från:
http://www.noiseaddicts.com/2008/11/beatles-hard-days-night-mystery-chord-solved/