bach is free and open source: it is licensed under the GPLv3 license, and hence you are free to use it in any GPLv3 project (contact us for commercial use).
We can afford to keep bach free thanks to the generous donations of our supporters on Patreon. If you find bach useful, please consider becoming a patron.

bach is cross platform. Whether you're running OSX or Windows, you can experience the full power of computer-aided composition.

Even if you aren't a fan of music notation, bach might still help you by adding two new data types to the Max environment: rational numbers and lllls (Lisp-like linked lists). The latter can contain other lllls, a bit like a Lisp list. Unlike Max lists, bach lllls have no limit in size, an essential feature to deal with long collections of data.

Are you a Max externals programmer? You may be interested in the bach public API in the download page.

bach implements both classical music notation and proportional music notation, with support for accidentals of arbitrary resolution, rhythmic trees and grace notes, polymetric notation, MusicXML, MIDI files and much more. The graphic position of all notation elements can be queried so that reactive customized notation systems can be built.