What is a guitar EQ pedal?
Guitar EQ pedals are one of the most misunderstood effects you can buy. Because they are often one of the more expensive pedals available, people expect a drastic change in their tone. The fact is guitar pedal EQs, are used to enhance your tone if you know something is missing. They produce subtle changes that many people won't even hear. However in the hands of an armature, a guitar EQ pedal can trash a decent tone. As you begin refining your guitar sound, you may find that there is something specific you are missing. Perhaps your tone rolls off on the low end, and you would like to add a little punch to your power chords. Maybe you sound is a little muddy and you'd like to brighten it up a little bit. Regardless, when used properly the controls of an EQ pedal will not move drastically off unity. They are intended to cut or boost very specific frequencies.
Less is more:
As a general rule of thumb, if you are unsure about how to attack a frequency issue, begin by "cutting" frequencies or taking them out. Too much compensation on the EQ can make your signal muddy. Instead start by taking things out gradually. It's also important to remember that there are some things an EQ pedal just can't fix. You are not going to magically get MESA Boogie sound out of a cheap amp just by boosting the lows. If you are unsure how exactly an EQ pedal will affect your tone, try one out at the guitar shop before you buy it.
Acoustic guitar EQ pedals:
Guitar EQ pedals are not just for electric guitar. They can be used in many of the same ways to shape the tone of the acoustic guitar. However the major difference between equalizing an electric guitar and an acoustic guitar is the problem of feedback. Because of their hollow bodies, acoustic guitars have a tendency to feedback. By rolling off specific frequencies (usually 100-110Hz for low hums, and 1-1.6k for high feedback) you can help control your guitars response to the venue.
Another use for many guitar EQ pedals on the market is a level boost or cut. While there are better boost pedals on the market, if you want a quick level cut to fade into the background of a song, or a slight boost cut through with a solo, guitar EQ pedals can double in functionality. Just be careful not to boost the frequencies back that you eliminated for hum or feedback.
The industry standard guitar EQ pedal is the Boss GE-7. It is a 7 band graphic equalizer built into a rugged and compact stompbox. It also features a boost or cut of +/- 15db which is perfect to help that solo to cut through. Frequency response ranges from 100Hz to 6.4Khz for nearly complete control of all audible frequencies.