In the last years of the 1970s, Terry Riley seemed to be everywhere; it would not have been unusual for a Riley fan in 1979, through only a moderate amount of travel, to catch him in two different cities in different months of the year. At this point, Riley was delivering hours-long concerts, no two the same, playing from the advertised start time until the hall was no longer available for the evening. Riley was utilizing a Yamaha Organ, modified to accommodate two outputs, and a secret weapon, "The Shadow," a box built by Chester Wood that was an early digital delay. It was used in addition to the ancient Revox tape delay that Riley had employed for more than a decade in concerts that, by this time, invariably began with Riley stating, "I do have a tape recorder up here, but there is nothing on the tape. I use it to create some of the loop effects that you will hear tonight. Everything you will hear me play will be live."