In digital recording, we are constantly on guard to avoid clipping, no exceptions. As a result, those who are new to digital recording may tend to record at levels that are too low, or fail to bring up the final level to where it should be. As a result, the overall level can sometimes be too low, soft parts of the music get lost in the mix, or either is compromised by noise in the system. This problem may also be encountered in a mastering situation. In any event, if the mix is too low to suit your tastes, there are solutions to bring up the overall level and retain the musicality of the recording.
While it is tempting, and often the most common solution to use the normalize function in your audio editor, it is not the most preferable one. Along with bringing up the level of the track, you also increase the noise accordingly. A good way to bring up a final level in a way that usually produces much better results than normalizing is to use a limiting plug-in, such as the Waves L1, which we will use in our example. (Of course, any good limiter plug will do.)
If you have access to a psycho acoustic analyzer (no, not an insane acoustician) such as Waves PAZ, It’s easy to see graphically where the peak (the point of highest volume) is. For example, let’s say that the highest peak is 7.2dB below the maximum possible amplitude (level). Adjust the limiter’s threshold, (in this case, the L1 or L2) to the same value. This achieves similar results to normalizing but with a far better overall sound. (Due to the L1’s superior processing engine.) If the overall volume you have achieved is still not satisfactory; push the volume up a little more. Using the normalize function won’t do anything since we’ve already used the maximum possible dynamic range. You could use the gain function in your audio editor, but this will result in clipping. (Clipping bad… limiting good, or at least not so bad…) The L1, being a limiter, can push the volume up without clipping: Adjust the threshold setting to the value of desired gain (A threshold of 9dB results in an overall 9dB gain in volume). The music should sound unchanged, except for being louder.
A note on limiting: To limit or not to limit is a musical choice. Some musical styles apply heavy limiting while others don’t, and some engineers and producers overuse limiting (more is better, right?) to the point where there is now a backlash against it in some parts of the recording industry. Production requirements may suggest limiting is needed, for example preparing your music for broadcast might necessitate limiting in order to compensate for the radio’s smaller dynamic range. In the example an exaggerated limiting setting was used. In the real world, limiting to produce 5.2dB attenuation is a bit heavy. Normally we should keep the maximum to about 4dB attenuation, but careful use of your ears should be what dictates the right amount for your music.