Originally posted by Mixerman from R.A.P.
It can be hard to put into words some of the more abstract characteristics of why we do what we do when shaping the tone of multiple sounds into something that resembles music. What follows is a very practical way of thinking about how to use eq effectively.
30Hz super duper low, often referred to as subs up to 60hz These are dangerous frequencies to be playing with.
50Hz super low
100Hz pretty low and beefy, easily replicated in a 6" speaker
250Hz the start of the lower mid range, woofy, not a clean low end, sometimes to much of 250 is too thick. However, it is the range of bass that will replicate well in a 2"-4" speaker, so you don't want to eradicate it.
500Hz lower mid range, often accused of sounding boxy.
750Hz getting towards the upper end of lower mids. Also slightly boxy, tends to reduce clarity, however, it can also add presence in the right situation.
1kHz this is the beginning of the upper mid range, it is a very present frequency as it is so close to the peak of hearing.
2kHz This is our most easily heard frequency as humans. Too much of this and harsh will be an adjective you'll hear allot. It is the end of the presence frequencies. 2K has been accused of adding bite.
3kHz Much like 2k, it adds bite. In my opinion it can be even more harsh than 2k.
6kHz Now we leave the bite aspect, and we're into dentist drill territory. This frequency can give you a nasty headache quick.
8kHz Now we are leaving the mid range territory, and entering high-end territory. This is the most present high-end frequency. It can be useful for brightening, without adding high-end noise.
10kHz Now we're really into high end. This is on the lower end of high end. The addition of this can be helpful in opening up a sound, and reducing he coloration of a microphone, or processing.
15kHz This is very high end. It will often add artifacts as quickly as it will open up a sound. When adding high end, it is recommended to try adding 10k, 12k, and 15k and decide which helps the most. When you're 60, you probably won't hear this very well anymore. Or, maybe you'll hear it all the
time.
20kHz Don't mess with this. It's way too high.
EQ's boost and cut more than just the frequency that is selected. You can usually adjust the amount of frequencies you are affecting with the boost and cut by the "Q". The "Q" adjusts the amount of frequencies that you are adjusting with your boost or cut. The selected frequency will get the majority of the boost, and will be in the middle of all the frequencies affected. This is called a bell curve.
The boost and cut are usually in db increments. A typical EQ can boost or cut in the range of 12db. A great way of learning exactly what characteristics a frequency has, is to boost between 8 and 12db and sweep the frequency until you find a very offensive frequency. Then cut that frequency to taste. After a while, you'll figure out what the characteristics are of certain frequencies from this method.
I hope this helps.
Mixerman
