When using time-based effects such as reverb, it is important to know how long the beats are in your track. This will help you time your reverb tails more precisely to avoid masking and muddiness caused by excess reverb. For instance, if you are using a big reverb for a snare drum, you can have the reverb disappear just before the next snare drum hits. Not only will you have cleaner mixes but the reverb will sound more controlled instead of having excessive overlapping of the effect.
Here are some common tempo’s with their beat durations…
*based on 4/4 time signature*
to calculate ½ beat, divide duration by 2
to calculate ¼ beat, divide duration by 4
to calculate 2 beats, multiply duration by 2
to calculate 4 beats (1 bar), multiply duration by 4
To calculate the length of a beat at any given tempo use this formula:
A. BPM / 60 seconds = beats per second
B. 1 second / beats per second = length of 1 beat
Not only is it important to know the duration of 1 beat for reverb tails, it also becomes important when rhythmically dialing in LFO modulation such as Auto-pan, LFO tool and Max for Live’s LFO device.
Hertz is a unit of measurement meaning “cycles per second”. To calculate how many cycles per second based on beat duration, use this formula:
A. 1 beat / beat duration = beats per millisecond
B. beats per millisecond X 1000 milliseconds = beats per second (cycles per second)
For example, if my beat duration is 500 ms.
1 beat / 500 ms = 0.002 beats per millisecond
0.002 beats per millisecond X 1000 ms = 2 beats per second
2 beats per second X 60 seconds = 120 beats per minute (BPM)