These are two .mp3 files, one with SC1 and another with SC2 Terran songs, high quality played on guitar, which you can use as custom radio in game or just listen by itself.
Total of 32 minutes, mixed in Audacity, which can be played in loop.

It's quite cool to play the game listening to these songs.
Just setup your Mixtape path at the game launcher under "Custom Music Paths", drop the file in the folder you choose as Mixtape, and select the Mixtape radio in game.