Have you ever wondered what it means when you see "mastered by" credits given on your CD's ? Here's a brief overview of the process.

Mastering is done on the two track master that is your final mix from the studio. Mastering engineers (versus mix engineers) will use "multiband" compressors..i.e..they only work in frequency ranges that they select..so if your mix is a little boomy, they can compress the low end and leave everything else unaffected. They also use very high quality parametric e.q.'s to touch up a mix. Remember, the mixing engineers are very good and don't send junk (usually) to be mastered. Many master engineers use gear that will add spaciousness to the sound..imaging. The mastering engineer's job is to fix any problems on the studio two track mix and to prepare that mix for release to different mediums. He might make a mix for the CD duplication plant that will have a wide dynamic range compared to a mix he (or she) prepares for radio. Radio mixes have to be compressed heavily due to the limitations and laws of FM and AM radio. I have heard of separate masters for European release. Overall, having your recording mastered will give it a polished, smooth, and present sound.

When I mix for a project that will be mastered, I never use compression on the stereo mix..it always sounds raw to me leaving the studio since I am used to doing demos where we "quasi-master" in house. On demos that are not mastered, I always send the stereo mix through a tube compressor right before the DAT and compress it according to it's intended purpose or the customers request. We do many songwriter demos where the recording will be pitched and listened to on small speakers; often the customer wants heavy compression so they can turn the playback volume up without fear that any loud or piercing notes will come through and annoy the listener.

One other thing..mastering engineers can add fades and eliminate any noise prior to the start of the track..this used to be done in the analogue domain, but much of it is done via hard disk and a number of software programs. They can also add the codes needed for CD duplication. By the way, the TC Finalizer is an amazing piece of gear that has put basic mastering into the hands of a project studio. The one thing you can't replace, though, is the ears of the mastering engineer! That is why only a handful of mastering engineers do the vast majority of major label releases.

Chris Hugan runs Fatback Recording and is the Creative Director for Pigworks Music, both located in Nashville, TN.