Demystifying Mastering Home Recordings
Mastering can turn your already-good music into a truly great CD. The mastering process of recording involves preparing your music for duplication. Several steps are involved in taking your songs from individual, mixed tunes to part of a whole album.
First, you need to optimize the dynamics and tonal balance of each song, and then you need to process the songs so that they are matched in volume to each other. These steps usually involve doing some EQing, compressing, limiting, and sometimes expanding to the songs.
You also need to sequence your music so that you have the songs in the best possible order and you have the appropriate amount of time between each song. Your last step is to put your mastered music onto a format that enables you to duplicate it.
No matter how well you recorded and mixed your music, you still need to do some processing during the mastering stage. This usually consists of adjusting levels with compression, limiting, and EQing and using additional processing if necessary.
The purpose of the processing stage is to balance the overall tonal characteristics of each song and optimize the dynamics of each song so that the songs are at their best overall volume. You can achieve these goals by using the following tools:
Compression: Some music sounds best when it’s smooth, and other music is much better when it has a punchy quality to it. Judicious use of compression can produce either of these effects. A good mastering engineer knows when and how to make music punchy or smooth. (Sorry, you can’t have both at the same time.)
Adding compression to the mastering process is an art. Too much or the wrong type of compression makes your music sound flat. Too little, and your music may sound weak.
Limiters: If any instruments are too loud in comparison to the rest of the mix, a limiter can tame them so that the difference between the song’s peak level and average level is optimal. This difference varies depending on the style of music, but it should never be less than 6dB and is usually between 12dB and 18dB.
EQ: Because you recorded and mixed each of your songs individually over a period of time (often a long period of time), each song probably sounds a little different. Some may be brighter than others and some may be heavier on bass, but one thing’s for sure — each has a different tonal quality.
For your compilation of songs to work as a unit, the songs’ tonal quality needs to be somewhat consistent. The songs don’t have to all sound the same, but they do need to work well together. The mastering engineer uses multiband EQs on each song to make them work as separate songs and gel as a complete artistic statement.
Sequencing involves putting your songs in the order that you want and setting the blank space between each song so that the CD flows well from one song to another. Because a CD is supposed to represent a cohesive body of work, this is one of the most important aspects of mastering.
A crucial aspect of mastering a CD is getting the levels of all the songs to be the same. After all, you don’t want your listener to have to adjust the volume of his stereo from one song to another. Having consistent levels from song to song helps with the cohesiveness and flow of a CD. This is done with simple gain adjustments, compressors, and/or limiters.