 Jacob designed the sound to include unseen, offstage performers for some parts, and he specified a Mellotron keyboard sampler fitted with tape loops of pre-recorded arrangements such as cello and brass parts, the backwards tape sounds emulating "I Am the Walrus", and "musique concrète" elements to mimic the Beatles' sound collage "Revolution 9".Jacob specified that the piccolo trumpet part in "Penny Lane" would be panned around the room to four speaker locations, an enhancement to the Beatles' stereo recording.To produce the uniquely repetitive "Shuk-k-ka" sound at the beginning of "Come Together", Jacob and New York sound mixer Larry Spurgeon used an Eventide Harmonizer set to delay mode to work out a method which must be repeated by hand at every performance.