The purpose of Discreet Music, according to Eno, was to create a piece of music that could simultaneously be heard and ignored. Released in 1975, this album is Eno's first experiment with generative composition based on algorithms. A synthesizer played back two melodic phrases, which were then run through a graphic equalizer, an echo unit, and finally recorded onto a tape machine. The output of this recording is fed via a delay back into another tape machine, which records the overlapped signals and outputs them to the monitors.
First utilized by the duo of Robert Fripp and Brian Eno in 1973, this tape loop process became known as Frippertronics. This technique produces unique patterns and rhythms as the music changes each time it is passed through the loop. This analog process eventually gave way to digital application of generative, algorithmic music.