Exporting Mix for Mastering in Reaper:
- Open your mix project in Reaper.
- Go to the File menu and select Render.
- In the Render window, set the following preferences:
- Sample Rate: 48 kHz
- Bit Depth: 32-bit float
- Channels: Stereo
- Dithering: Disable dithering
- Choose the destination folder and enter a file name.
- Click Render to render and export your mix with the specified settings.