What Is Mastering?

There are three basic stages of the recording process: recording, mixing and mastering. The recording stage is when all of the material (guitars, drums, bas etc) is recorded onto individual tracks. Microphones are set up, and the musicians do their thing to get all of the audio recorded into a DAW (digital audio workstation), digital multitrack or (if you’re a fan of vintage recordings) a tape machine. The mixing stage is when all the levels and panning of each track are set, and effects are added to individual instruments and the whole lot is mixed down into one stereo file. Mastering is the somewhat “dark art” of adding the finishing touches to the stereo file to bring it up to a commercial volume, and provide that added polish that makes it sound like a professional release.

The Processes

Mastering basically just involves two main processes: EQ and compression. Extra processing such as stereo widening and even a little mastering reverb can also be used to add a bit of depth and colour to a recording, but it’s the EQ and compression that are the most important.

Any equalisation added to a final mix has to be very precise; as you’re not working with individual instrument tracks, a slight tweak to enhance a vocal part will affect anything else in the song that occupies the same frequency range. Therefore when applying EQ in the mastering stage it’s important to listen to the whole song, rather than focusing on just enhancing one particular element.

Compression is most often used to give the whole track a bit more power and volume, and multi-band compression can be used to compress different parts of the frequency spectrum with different parameters, allowing the mastering engineer to “even out” the spectrum in terms of dynamics. Limiters are used to boost the perceived volume of a track; and this is where the tricky issue of the loudness war comes in. The louder a song is perceived by the end listener, the intrinsically “better” it sounds. But the louder you make a song through compression and limiting, the less difference there is between the loud and quiet parts of the song. This reduction in dynamic range is not musically desirable, so the key is to find a balance whereby the song is at a commercial volume but all the dynamics aren’t squashed to 0db.

Mastering Services

For really high-end mastering specialised analogue equipment is needed. But the more fancy equipment an engineer needs, the higher the price of mastering. For analogue and hardware based mastering you typically won’t be able to find anywhere charging less than £25 per track, and prices can reach into triple figures for the best mastering suites. However, digital mastering can still provide excellent results. The cheapest price out there for digital mastering is £10 per track, and the results can be excellent for the money. If you’re choosing a mastering service, make sure you pick one that offers you a free sample of your own work. This try before you buy approach reflects a confidence that the engineer has in their own work, and gives you a chance to hear whether your music would really benefit from professional mastering.

To view Amati’s own mastering service click here.