CLM (originally an acronym for Common Lisp Music) is a music synthesis and signal processing package in the Music V family created by . It runs in a number of various Lisp implementations or as a part of the audio editor (using Scheme, Ruby and now Forth). There is also a realtime implementation, which is developed by Kjetil S. Matheussen. This software was used to digitally stretch Beethoven's 9th Symphony to create 's 9 Beet Stretch.