Preview channel strip in the Logic Pro for Mac Environment
When you audition audio in the Project Audio Browser and in the Audio File Editor, the source audio that you hear plays through the preview channel strip. Logic Pro for Mac creates the preview channel strip automatically in each project—you can find it to the right of the highest-numbered audio channel strip in the Environment. You can use the preview channel strip in a variety of ways to set the volume of the audio you are previewing, add audio effects just to the audio you are previewing, select outputs for previewing audio that are separate from your main outputs, and so on.
No other channel strip can play audio from the Project Audio Browser or Audio File Editor. Also, you cannot create another preview channel strip if you delete it.
If you delete the preview channel strip, the highest-numbered audio channel strip in the Environment is automatically used to play audio from the Project Audio Browser and Audio File Editor as well as the audio track assigned to play back through that channel strip. Depending on how you have adjusted that channel strip, this may result in the audio you play back from the Project Audio Browser and Audio File Editor sounding significantly different than they would unprocessed. Therefore, you should avoid deleting the Preview channel strip, and access it only to adjust its controls or add effects.