SoundCloud is an online audio platform that enables people to send, receive, play, and distribute music, and also engage in conversation about the music. The platform is designed to meet the needs of professional musicians. Music can be distributed in downloadable or streamable formats, to individuals or groups of people. Conversations about the music are facilitated by a capability to insert comments relating to a specific location within a sound track (see the SoundCloud Tour for an illustration of this innovative feature).
SoundCloud provides an open, standards-based API backed by the SoundCloud Developer Manifesto. The Manifesto describes objectives and principles "for developers inside, outside and around SoundCloud" and welcomes the participation of outside developers in building upon the foundation the API provides.
The API exposes the full range of SoundCloud's functionality for third-party developers. Developers can upload tracks, access comments and tracks, edit metadata and more.
The API is RESTful, and supports XML and JSON. The API provides resources including users, tracks, assets (audio tracks), comments, and events. As Chris Messina notes, the SoundCloud API supports OAuth as well.
See our new SoundCloud API profile for more details.
The SoundCloud API documentation includes a developer docs wiki and sample code. The SoundCloundAPI Google Group is available for open discussion, and developers are also encouraged to contact the SoundCloudAPI directly with any questions.
Developers have already applied the SoundCloud API to develop some interesting applications, including the app RadioCloud, a radio mashup that visually integrates a user's social graph, and a Facebook SoundCloud Player. Note that both these apps have source code available, RadioClouds is ActionScript and the Facebook player is PHP. More at our SoundCloud Player for Facebook and RadioCloud mashup profiles.
With features like like the ability to tie conversations to a specific location within a music track, SoundCloud and the SoundCloud API open new ways to match professional-level customizable music distribution capability along with a new kind of social networking.
Update: SoundCloud has offered 100 PW readers an invite to their private beta, just go to http://soundcloud.com/guestlist/programmableweb to sign-up.