Sony Acid Pro 6: Sync Music Files With An Acid Project’s Tempo, Or Vice-Versa

OBJECTIVE: Beatmap long, unlooped files so that they can match up with loops.BACKGROUND: Acid typically uses relatively short loops to create projects. However, it’s possible to import long files—even ones with slight tempo variations—and add markers so that the file plays back in sync with the rest of the project, or the project tempo syncs to the file.


  1. Drag the file you want to beatmap into an Acid track.
  2. When the Beatmapper wizard appears, click Yes, then Next.
  3. Move the downbeat marker to the file’s first beat, then click Next. Note: The Play and Stop buttons let you audition the file shown in the Beatmapper.
  4. Acid estimates the length of one measure. Adjust the end marker to define the exact end of the measure. Zoom in if needed with the (+) button to position the measure end as precisely as possible.
  5. Click on the Play button to verify that the highlighted region loops correctly, then click Next.
  6. Click on the Play button again, then click on the > button (or click within a measure) to step through each measure and verify that its start and end points are set correctly. When they are, click on Next.
  7. The file is now beatmapped, and the wizard shows three options: Change Project Tempo to Match Beatmapped Track (if unchecked, the Beatmapped track follows the existing project tempo), Preserve Beatmapped Track Pitch When Tempo Changes, and save Beatmapper Information with File. Check the desired options, then click Finish.


  • Acid assumes files over 30 seconds are not loops, but you can change the default time under Preferences > Audio Tab, in the top right field. 
  • Starting with Step 4, you can enable a metronome sound as a rhythmic reference.
  • Select a clip after Beatmapping it; click on View > Clip Properties, then click on the Save button to embed the Acidization information in the file. Click on the Stretch tab for beatmap editing without having to invoke the Beatmapping wizard.