I operate SafeandSound Mastering, a low cost, professional mastering facility. Mastering is the final tweak on music mixes before they get released. A mastering engineer ensures the music is sounding as good as it possibly can for all the different playback systems it will encounter. In addition it's a quality control stage for music before it is released into the wider world for distribution online, artists websites such as Myspace and Reverbnation and of course the many online based record labels.