Sally's Dream is a piece based on the contours of human sleep.
The piece follows the natural sleep duration, lasting 8 hours, and is based on its different stages and cycles.
Like human sleep, the piece is divided into four cycles and within each are the three different stages of sleep: light sleep; deep sleep, and paradoxical sleep. These cycles and their stages respect the necessary length of healthy sleep.
Each state presents some specific musical materials:
Light sleep, during which eye movements stop, and brain waves become slower. This stage is known for keeping the ears active. Therefore, the listener can hear recordings of the room, guitars, and noise of the street outside the studio.
Deep sleep is characterised by slow brain waves called "delta waves" interspersed with smaller, faster waves. It is the stage where the brain is less active. Therefore, the material for this section is comprised of mostly constant static noise and low frequencies, recreating the atmosphere of the deep ocean. However, one might hear far echoes, like silent ghosts passing as chimaeras. These moments rarely appear (5 minutes in one hour).
In paradoxical sleep, your eyes move behind closed eyelids. Mixed frequency brain wave activity becomes closer to that seen in wakefulness. Dreams occur in this stage. The listener will hear a considerable amount of different sound material from the most expected sounds to the strangest, from the beautiful to the scariest.