REAPER is a digital audio workstation for Windows, macOS and Linux. It records and edits multitrack audio and MIDI, hosts instruments and effects, and mixes projects into finished audio files. Its tracks can hold different media types and route signals between one another, so a project can combine microphone recordings, MIDI performances, samples and sound for video.
There is one fully featured edition, with a full-function evaluation lasting 60 days. Discounted and commercial licenses provide the same application. The discounted license covers personal use, educational and nonprofit organizations, and commercial use where annual gross revenue does not exceed US$20,000.
Recording and comping takes
A REAPER track can record an audio or MIDI input, or capture its own processed output. Recording before effects preserves the incoming performance, while recording the processed output captures the result of the track’s processing. Input monitoring can include software effects, and separate monitor mixes can have their own processing. The number of simultaneous recording inputs depends on the connected hardware.
Loop recording, overdubbing and punch recording provide different ways to build a performance. Track lanes keep alternate takes or layers within a single track. With swipe comping, you select passages from several takes to assemble a composite performance. Crossfades join the selected passages, and A/B comparison lets you compare alternative composites.
Razor edits
REAPER’s arrangement tools work on both media and the automation that changes controls over time. Razor edits select sections of these elements for cutting, moving, copying or stretching. This allows a passage and its associated control changes to move together, or lets you edit the automation independently of the recording.
Individual media items can be split, trimmed, looped, faded and crossfaded. Time stretching changes duration, while pitch shifting changes pitch; the available processing engines also include modes that preserve vocal formants. Regions collect passages that can be copied or moved to try another arrangement. Audio, MIDI, video and still images can share the timeline, with tempo and time-signature changes managed within the project.
Signal routing
Routing determines where each track’s signal travels before reaching the final mix. REAPER supports up to 128 individually routable audio channels per track, alongside MIDI buses. Nested folders combine track organization with group editing and bussing, allowing related tracks to feed a shared processing path.
Track, take and plug-in controls support automation recording, playback and editing. You can make a control follow changes across a passage rather than leave it at one setting for the entire project. For surround work, the included ReaSurroundPan places signals within configurable speaker arrangements, using a spatial view to control their position.
REAPER’s effect chains
REAPER includes processors such as the ReaEQ equalizer, ReaComp compressor and ReaVerb convolution reverb. ReaTune provides automatic and manual pitch correction. Effects can run during playback, or their output can be rendered non-destructively. Automatic plug-in delay compensation accounts for processing latency when combining signals.
FX containers package a chain of processors together with its routing and parameter mappings. You can save and recall that arrangement, then run containers or individual plug-ins in parallel.
Third-party effects and instruments can extend these chains. REAPER hosts VST, VST3, CLAP, LV2 and JSFX plug-ins, with Audio Units on macOS and DirectX plug-ins on Windows.
MIDI instruments
Recorded or imported MIDI can drive virtual instruments or be routed to MIDI hardware. REAPER includes the ReaSynth synthesizer and ReaSamplOMatic5000 sample player, alongside MIDI processing tools. A project can therefore combine recorded sound with parts whose sound comes from an instrument plug-in.
Retroactive MIDI recording retrieves MIDI that was played even when the track was not armed for recording. MIDI and audio routing remain part of the same track system.
Rendering finished audio
Rendering can produce a complete mix or separate files from tracks, regions and media items. The Region Render Matrix associates chosen tracks with chosen regions, controlling which combinations become files.
REAPER lets you choose output channels and encoding settings, queue render jobs, and build filenames from project attributes through wildcards. Audio output formats include WAV, FLAC, MP3, Ogg Vorbis and Ogg Opus. Loudness normalization and true-peak limiting can be applied during rendering.
An HTML render report shows loudness over time and identifies clipping. A dry run can generate those measurements without writing the finished media files, allowing you to inspect the proposed output before producing it.
Customizing REAPER
REAPER exposes thousands of operations as actions. Individual actions or sequences can be assigned to shortcuts, toolbar buttons or external controllers. Saved screensets recall window arrangements, while configurable toolbars and layouts place the controls needed for a particular task within reach.
ReaScript extends this customization with Lua, EEL or Python scripts. Integrated tools support writing, editing and testing them, so repeated project operations can become a custom command. JSFX provides a separate scripting environment for creating or modifying audio and MIDI effects.
