When the band performed the song live, they made the following changes to the song: • The pace of the song was slower and more deliberate, creating an even more sombre atmosphere than the studio version. •
Richard Wright almost always used Farfisa organ in place of piano (the exception being their performance at
KQED studios in San Francisco on April 29, 1970, in which the studio had a piano). •
David Gilmour played electric guitar and performed a guitar solo over where the scat solo occurred in the song. • In the spring of 1970, the key of the fadeout section was changed from E-minor to B-minor. During this section,
Roger Waters would bang a gong instead of bongos as the music faded away. After the B-minor section, the band presented a selection of sound effects such as footsteps and creaking doors, courtesy of the
Azimuth Co-ordinator they employed on stage. The effects represented the "nightmare", which would conclude with the sound of a loud explosion. Thanks to the panning sounds created by the Azimuth Co-ordinator, the sounds would surround the audience and the footsteps would move from left to right through the back of the venue. • By mid-1969/early 1970, the band would follow the instrumental and/or sound effects section with a repeat of the third verse ("The lines converging where you stand..."). ==Personnel==