How does Cubase backup reduce file size?

Cubase
1

I just backed up twelve short audio tracks (choral music). After Backup, the original file went from 298 MB to 165 MB.
Before I backed up, I had already emptied the trash and removed .BAK files.
So can anyone tell me exactly what was removed to gain this reduction in file size? Were the .wav files compressed?

2

It probably got rid of unused audio files, and edit files.

Of course, wav files are not compressed.

3

OK, thanks. But I’d already removed the files not used in the project and emptied the pool trash.
It seems like a big reduction. What are edit files?

4

See Audio Files and Audio Clips

5

Thanks, then.
Have a good evening.

6

You’re welcome! It’s still morning here :sunflower: