View Full Version : what to look for in a Equalizer...

07-05-2005, 02:22 PM
I would like to know what I should look for in a Equalizer. I kno almost nothing about them. So any sites that explain them a litle better would be fantastic.

Thank you

07-05-2005, 02:49 PM
Equalizers are normally used to fine-tune a system, and should be
treated as such. Equalizers should not be purchased to boost one band
12dB and to cut another band 12dB and so on - excessive equalization is
indicative of more serious system problems that should not simply be
masked with an EQ. However, if you need to do some minor tweaking, an
EQ can be a valuable tool. Additionally, some EQs have spectrum
analyzers built in, which makes for some extra flash in a system.
There are two main kinds of EQs available today: dash and trunk. Dash
EQs are designed to be installed in the passenger compartment of a car,
near the head unit. They typically have the adjustments for anywhere
from five to eleven (sometimes more) bands on the front panel. Trunk
EQs are designed to be adjusted once and then stashed away. These
types of EQs usually have many bands (sometimes as many as thirty).
Both types sometimes also have crossovers built in.

Generally, companies that produce 1/3 octave (30 band) and 2/3 octave
(15 band) equalizers are good. These include AudioControl, USD, Rane,
Phoenix Gold. Most people try to stay away from equalizers that
contain a "booster;" these are made by Kraco, Urban Audio Works and


07-05-2005, 02:57 PM
if you want a good EQ that is not priced too badly, check out the Arc Audio PEQ, it is a 7 band. the Zapco SP4 is a 4 band EQ, but it is still better than the PEQ, but the zapco is maybe 40 or 50 dollars more. i have used both of these EQ's before. also, the arc audio XEQ might be something to look into. those are all dash mounted EQ's. if you want a trucnk mounted EQ, i think Audio Control is the way to go.

07-05-2005, 04:35 PM
First thing to understand is the different types of EQ's;

Parametric EQ: This is an equalizer where the level of boost/cut, center frequency and "Q" can all be adjusted by the user (you). Center frequency is the frequency (or "band") that you are adjusting. Q is basically the slope (or "width") of frequencies around the center frequency that are affected. When you boost/cut a frequency, you are not only boosting/cutting that specific frequency, you are also affecting a certain bandwidth of frequencies around that center frequency. The lower the Q, the wider the range of frequencies around the center frequency that are affected by the boost/cut (say, for example, if your center frequency is 500hz, all the frequencies between 250hz and 750hz may be affected). The higher the Q, the narrower the frequencies around the center frequency that are affected (again, with 500hz center frequency, only 400hz to 600hz may be affected). And the wider slope (lower Q), the more shallow the slope, so the surrounding frequencies will be affected more by the boost/cut than with the narrow (and steeper) slope, which is the higher Q. Sufficiently confused yet?

So, if you boost 500hz by 3db with a low Q (wide, shallow slope), 475hz and 525hz may be boosted aswell, but by only 2.75db. 450hz and 650hz may be boosted 2.5db. 400hz and 600hzmay be boosted by 2db. etc etc. But, with that same 500hz center frequency and 3db boost with a high Q (narrow, steep slope), 475hz and 525hz may be boosted by 2.25db. 450hz and 550hz may be boosted by only 1.75db. 400hz and 600hz may be boosted by .75db. Etc etc. This is all just for example to show you the differences......but it should make it easier to see how the Q affects the surrounding frequencies

Graphic EQ: Center frequency and Q are fixed, boost/cut is the only available adjustment. Pretty straight forward here.

Parametric EQ's generally have less bands because of their greater flexibility. They can be more helpful than graphic EQ's because they allow you to target specific problem areas with much greater accuracy. Graphics EQ's generally have more bands, but are less flexible and helpful if you want more broader control over basically the entire frequency spectrum.