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Compression is an important tool that can aid in creating great mixes where all the parts fit comfortably together. By limiting the dynamic range, especially of critical elements like the vocals and the bass, we are able to maintain the pres- ence of those elements without resorting to boosting their overall levels in order to keep them prominent. We don’t want the vocal or the bass to come and go, leaving gaps in their critical role of propelling the music. Generally, when used to gently control dynamics, compression is relatively transparent; we aren’t aware of it altering the sound except as a subtle control over the dynamic range. I will be covering more on this important function in the chapter on building a mix, but here I want to focus on compression when used to produce a more pronounced and obvious effect. The most common use of compression in this way is on the drums.

Quick Guide to Great Mixes and Masters

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Drum compression can define the sound of a popular music mix and it can also be a source of over-compression. Some amount of drum compression is used on most popular music mixes (including samples that have had compres- sion used when they were first mixed). Drum compression helps maintain the presence of the drums, as just described regarding vocals and bass, but it is also used in a more extreme fashion to dramatically alter the sound of the drums. This can be appropriate to a particular genre and generally pleasing (as well as powerful and dramatic) or it can seem overblown and serve to undermine a natural musicality to mixes.

Individual drum tracks are often compressed, especially the kick and snare, but often the tom-toms, hi-hat, and overhead tracks as well. If there are room mics used for the drums, they are sometimes heavily compressed. Then the whole set might be sent through a compressor for overall compression (or par- allel compression, as explained in chapter 4). Because the overall mix of all of the instruments might be compressed and limited as well (see the next section on buss compression), the drums might go through as many as three distinct stages of compression. This might be fine, and sound great, but it might also be a source of over-compression, making the drums bombastic in a way that might initially provoke the “wow” factor but can wear the listener down over time (there is more on the effects of over-compression throughout this book).

On the website is a clip of the drums from a song, first with compression and then without. I have tried to approximately balance the levels, though it’s not possible to do that thoroughly—the compression alters the dynamic range so the overall levels will never be equivalent. Whether or not you like the end result, it is significant to note the extreme difference in sound between these two clips—compression has dramatically changed the sound of the instru- ment. I don’t think this takes compression too far for this particular song, and there are plenty of examples in contemporary music where there is substantially more drum compression than I have used here, but for some this may qualify as over-compressed. In any event, this is a long way from the kind of relatively transparent compression that we often use on vocals, bass tracks, and other mix elements.

Drummer: Kevin Hayes

Artist: Acoustic Son CD: Cross the Line Track: “Back from the Edge” Audio Clip 3.15 Drums with compression

Audio Clip 3.16 Drums with no compression

It is not hard to imagine how drum compression, taken to an extreme, along with compression on almost every other instrument in a mix, might pro- duce an overly compressed sound. Controlling dynamics can serve to make a mix much more listenable—allowing the featured elements to remain featured and the whole mix to gel—but it can also squeeze the life out of the music. Mas- sive compression provides initial impact, but creates music that assaults the ear,

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leaving no breadth of dynamic range to provide musical contrasts. As always, use these techniques to match your own taste.

WHAT NOT TO DO

Don’t adopt an anti-compression attitude.

I have found a tendency among some purists to adopt a “no compression” attitude to recording, mixing, and mastering. I appreciate the motivation, and I would certainly encourage you to limit your use of compression depending on the style of music you are working in and the sound that you want to achieve. That said, taking compression off the table as an aid in creating recordings prevents you from allowing your audience to appre- ciate the music that you have recorded to the fullest. Recordings will be listened to in a variety of situations, and many of them present challenges from ambient sounds—like in the car or noise coming from an adjacent room. By creating a more consistent presence, compression improves the listening experience. Accept the fact that recordings are not, and can never be, the same as live music, so do not try to pretend that you can reproduce the live music experience exactly as it was played live; use compression to make recordings be better recordings.