In general we just need 24 bit stereo wav or aiff files at the same sample rate you recorded the tracks at, peaking at -0.1dBFs maximum, with NO brickwall limiting or clipping (flat topped wave forms) on them. A full list of recommendations for digital mixes and file formats can be read here. Our preferred way to receive your files is via uploading to our Hightail Uplink at spaces.hightail.com/uplink/totalsonicmedia If you have a DropBox account “share” the DropBox folder you have your mixes in to steve@totalsonic.net If you use Google Drive please give access of the files to totalsonicmedia@gmail.com If you wish to use other services such as WeTransfer or SendSpace - please email us their download link for the files to us. If you prefer to use FTP please email us for host address, user name and login password to our server. Filezilla is a great cross platform freeware FTP client that we recommend. Please email us for our shipping address if you wish to send tapes, discs, or drives to us.