"Disco felon"... was reported to NEJM by Frederick W. Walker and other doctors at Johns Hopkins Hospital in Baltimore in July 1979. "A 17-year-old girl came to the emergency room complaining of an infected finger," they wrote. "Physical examination showed... a classic felon [a painful inflammation of the finger, usually near the fingernail] of the left middle finger... the patient had noticed a small crack on her finger... She thought that the crack might have resulted from snapping her fingers while she was disco dancing..."

The doctors treated the girl by draining and bandaging the inflammation. She recovered, but Walker and his associates sounded a dire warning to other disco dancers and their doctors. "Disco dancing may eventually be shown to damage a variety of body systems: namely visual, auditory, orthopedic, and nutritional. [Nutritional] damage might result from self-imposed starvation in an attempt... to wear the latest outfits."

Concret PH, the title being a reference to the architectural design and construction material, is a crackling two minutes of pointillistic sounds. Xenakis recorded the sound of burning charcoal, then layered and transposed the recordings to create evolving densities and ranges of snaps, crackles, and pops. This piece, along with Varèse's Poème électronique, remains a classic of the electroacoustic genre.