Make Your Drums Sound HUGE!
Compression in your mix serves two primary functions. The most common use for compressors is to wrangle in the dynamic range and manage the level of an instrument, vocal, or perhaps the entire mix. The second function is to change the tonality of the signal your processing. Give this a try on a drum track or something with a significant transient impulse. Make your level adjustments so that your peaks may have plenty of headroom. (Peaks landing no more than -6db). When patching and dialing in your compressor be sure you start at unity gain, meaning the device or plugin is only passing the audio rather than affecting it. Adjust your attack to a slower setting. This will delay the compressors response time. In order to “get out-of-the-way” of the other transients your release settings should be relatively quick. Then be sure to use a significant ratio such as 6/1 or more. Your next step is to reach for the threshold. The threshold will serve as the insertion point for the effect, so at unity gain you can expect 6db of gain reduction if your threshold is around -12db. If your compressor has an auto-makeup gain feature this can be particularly handy. If not you should boost the output stage of the compressed by 6db to catch your levels back up.
Due to the slow attack of the compressor, the initial transient impulse (the stick or beater on the drum head) will be passed without being affected. The decay of the signal however will be affected as the compressor engages. This will bring our the resonance and the ring of the drum shell. allowing for a fat sounding, sustained.
The manipulation of the ratio and threshold settings will directly result in the sustained fattening effect, while the attack setting will directly result in the initial transient impulse.
Do the Math
When using compression plug-ins you can often adjust your attack and release speeds by milliseconds in the plug-ins graphic user interface. Try this for a more musical sounding effect.
Based on your tempo in beats per minute you can calculate in milliseconds the attack time needed for your drum track compression effect to engage in musical note values i.e. 32nd, 16th, dotted 16th notes ect.
The formula is as follows: in 4/4 time 60 /tempo(bpm) = time in seconds for one quarter note
for example 60/85bpm= 1 beat .705 seconds i.e. one quarter = 705 milliseconds
To figure out the delay time for a given tempo, divide 60 by the tempo in beats per minute, which will give you the delay time for a quarter note in seconds. Simply multiply the result by 1000 to get milliseconds.
So, for example, at 120 bpm: 60/120=0.5 secs or 500 milliseconds. In 4/4 time the quarter note gets the beat, so quarter notes= 500ms, 8th notes = 250ms, 16th note= 125ms.