21.16 Stem Rendering Media Items
Stem Rendering can be applied to ease your CPU load.
Kind: concept (user-guide-section) Chapter: 21 Exporting Files, Mixing Down and Rendering Source: REAPER User Guide v7.70
Stem Rendering can be applied to ease your CPU load. The item(s) is/are rendered to a new track, whilst the original track remains but is automatically muted and its FX are bypassed. If you later wish to change the FX in a stem rendered track, you can delete it, unmute the original, and make your changes. To make a stem track:

- In the Track Control Panel area, right-click over the track number. 2. From the menu, choose Render/freeze tracks, then one of the Render tracks to … stem tracks
(and mute originals) commands. Your choices are mono, stereo or multichannel. The first of these will render to a mono item (as shown here). The second will always produce a stereo item. The number of channels produced when multichannel is selected will be determined by the number of channels that you have defined for the track. By default, REAPER tracks comprise just 2 channels. As well as track FX, any audio or MIDI received from sends from other tracks is included in the rendered material. Stem rendering is similar effect to freezing tracks . One difference is that stem rendering leaves both the rendered and the unrendered tracks in the project. If you do not wish to keep both tracks, consider using one of the Render/freeze freeze actions instead. Stem rendering is also available with an extensive range of options (such as output format and quality) using the File, Render... command. This opens the Render to File dialog box.