 He selected what he considered to be the best parts of these 24-track analogue recordings, and sampled and looped them on a Roland S770, triggered from his Atari/Notator sequencing system.These loops were then mixed to two tracks of another 24-track reel.A 24-track reel has a running time of 28 minutes, which meant that Brook had 21 tracks, with one having been sacrificed to SMPTE code, and each 28 minutes long, available for overdubs.