If you need help about making and exporting your stems, check this article : https://colorsound.zendesk.com/hc/en-us/articles/201016828-How-to-make-your-stems-for-stem-e-masteri...
- Formats : .wav and .aiff
- Resolution : 24 or 32 Bits ( no dithering )
- Frequency : 44, 48, 96, or 192 k
- Volume : -2 to -6 db ( master volume only )
If you have any doubt about exporting your track, you should export your file using the same resolution and frequency used when you first created your track in your application.
If you need more info, refer to your DAW ( digital audio workstation ) support and documentation.
Important : About .zip and .rar. The purpose of sending your folder in .zip format is only to allow the upload of your entire folder as one single file. Don't smash your files, it will damage them and we will not be able to revert damage, nor to use them.