REAPER is a powerful but sensible Windows application that lets you record, arrange, edit, and render multi-track waveform audio. REAPER provides an extensive set of features, but is a very small and lightweight application (the installer is less than 1 megabyte, and includes many effects and a sample project).

REAPER supports ASIO, Kernel Streaming, WaveOut, and DirectSound for playback and recording. It reads WAV, OGG, and MP3 files, and records WAV files. You can arrange any number of items in any number of tracks and use audio processing plug-ins (DirectX and Jesusonic). REAPER also supports volume, pan controls and envelopes per track, multi-layer undo/redo, and user creatable color themes.

Changes in REAPER v2.147 - March 28, 2008:
* fixed open copy/reverse item giving bad results when switching away during render
* fix for control surface plug-ins reading incorrect config with no input set
* JS/ReaNinjam/reaper_ogg now use new plug-in APIs to share code
* AIFC support, for PCM and floating point samples
* dev: plug-in API updates
* dev: plug-ins can register API functions
* dev: plug-ins can now be notified of actions, can register named action IDs
* dev: a new smaller API for adding file read support
* dev: context menu HMENU retreival
* dev: Undo_BeginBlock/Undo_EndBlock() for condensing undo changes of multiple actions
* dev: GetTrackInfo now can query mute/solo/recarm state of tracks