A trail mastering is recommended for anyone who does not yet know how to do it Song should sound at the end, or for those who know exactly where they want to go in terms of sound technology, but are still looking for a suitable mastering studio that can implement these ideas and wishes. A test master enables the individual to compare Mastering studios. This is particularly advisable if something fundamental has changed in the previous production. This can be, for example, the following: Recording in another studio, Replacement of hardware or fundamental changes in the mix.