The new SDK improves stream security and content uploading functionality, and modernizes the technology stack.
ECMAScript 2015 and CommonJS
The original version of the SDK was written in CoffeeScript, which is no longer a core technology at SoundCloud. This update provided us the opportunity to migrate our source code from CoffeeScript to ECMAScript 2015.
Web Audio API
The previous SDK neither provided a way to record sounds from Web Audio applications nor a way to upload Web Audio recordings. It shipped with a Flash component that handled recording and uploading of recordings. There was no way to specify an external file for uploading.
The new SDK ships with a recorder component that uses Web Audio and
The new SDK now includes a new player component. This component improves security for creator content and provides the improved playback stability.