subject: Dynamics Processing in Audio Mastering [print this page] Author: Mehrzad Mehrabanpour Author: Mehrzad Mehrabanpour
All of us like our songs to sound as loud as our favorite CDs in the market, as a matter of fact when you compare your music to other songs, the first difference that is most prominent is the loudness. Loudness masks every other aspect of a piece of music when you compare it to another; brightness, detail, warmth etc..
How does a mastering engineer make your song sound louder, and what is the price?
As we all know nothing can go above zero db in digital audio, in other words you can't make a digital audio louder than 0db, so how is it that the mastered CDs you have, sound that loud? The answer is you can only make loud masters out of an audio file that has loud transients, if the whole audio file has one steady volume, and it's as loud as 0db already, you can't make it any louder. For instance take a pop or rock song, if you look at the wave shape in a DAW you can see that the loud transients are mostly the kick drums. Now if you can make the kick drums smaller and raise the whole volume, or raise the whole volume while not letting the kick drums go any louder than zero, you will have an overall louder song. How do you achieve that?
The processors that do such thing are compressors and limiters. While compressors may let some transients escape, limiters won't let any transients pass the specified out ceiling hence they are used at the end of the mastering chain to keep everything below 0db.
As you know the difference between the highest part and the lowest part in volume of a specified sound wave is called it's dynamic range, and what I described above is called reducing the dynamic range. This is the price you pay while making your song louder in mastering; you loose your dynamic range, meaning everything sounds closer together in volume after mastering despite the efforts you made to adjust the loudness of the different instruments in your song while you were mixing. Although so many people like the fact that they can hear everything in their mix after mastering, so many people don't, anyway loosing the dynamic range is inevitable here.
One of the other processors that are used for dynamics processing other than the compressors and limiters are the multi-band compressors. What they do is they let you compress different parts of the frequency spectrum separately.
This is so useful in controlling loud transients in the midrange especially with the vocals and guitars, it also lets you compress the bass (kick drum and bass guitar) before your audio passes through the compressors hence giving more space to make the song louder without any fluctuation in the volume.About the Author:
M-mastering provides high quality mastering services to musicians nationwide. Visit www.m-mastering.com for more hints on mastering.
