PRESONUS Studio Channel [22/30] Operation

OPERATION

20 | PreSonus 2007

3.3 EQUALIZERS

The equalizer in the Studio Channel is like a Swiss Army pocket knife, with the ability to carve out unwanted

frequencies as well as tailor your tone to enhance your sound. The custom-designed amplifiers in the EQ deliver

sweet-sounding gain/cut for ultra smooth highs, deep solid lows and clear midrange. The mid-band of the EQ

section has variable Q for controlling the width around the center point of the selected frequency. High and low

frequency bands give you the option for selecting peak/dip or shelving frequencies. What follows is a brief

explanation of how an EQ functions as well as some charts to help you navigate the frequency range of various

instruments to assist you in quickly setting the best EQ for your recordings and to help you get the most out of

your Studio Channel.

3.3.1 What is an EQ?

An equalizer is a device that allows you to adjust the volume of a frequency or range or frequencies within an

audio signal. In its simplest form, an EQ will let you turn the treble and bass up or down, allowing you to

adjust the coloration of, let’s say, your car stereo or an iPod. In recording, equalization is a high art. Good

equalization is critical to a good mix. When used correctly, an equalizer can provide the impression of

nearness or distance. It can also provide separation between similar sounds in a mix allowing them to both

shine through the mix.

The Parametric EQ

The Parametric EQ and semi-Parametric EQ are the most common equalizers found in most recording and

live situations because they offer continuous control over all parameters. The Parametric EQ divides the

audio signal’s frequency range in bands, usually three to seven, and provides the same set of control

parameters for each band: gain, frequency width (Q), and the center frequency of that Q.

The Q

The Q is by far the most useful tool a Parametric EQ offers. By adjusting the width of the Q you can

attenuate or boost a very narrow or broad range of frequencies. Each has its benefits, let’s look at the

narrow Q first.

A narrow Q has obvious attenuation benefits for removing unpleasant tones. Let’s say the snare drum in your

mix has an annoying ring to it. With a narrow Q, you can single this one frequency out (usually around 1

kHz) and remove it. This is also known as a “notch” filter. By notching out the offending frequency, you can

remove the problem without removing the instrument from the mix. A narrow Q is also useful in boosting

pleasant tones of an instrument such as the attack. Take for instance, a kick drum. A kick drum resonates

somewhere between 60-125 Hz, but the attack of the kick drum is much higher at around 2-5 kHz. By

setting a narrow Q and boosting the attack a bit, you can achieve a punchier kick drum without overpowering

the rest of the mix.

A broad Q accentuates or attenuates a larger band of frequencies. The broad Q and narrow Q are usually

used in conjunction with one another to achieve the desired effect. Let’s look at our kick drum again. We

have a kick drum that has a great big low end sound somewhere centered around 100 Hz and an attack

hitting in almost dead on at 4 kHz. In this example, you would use a broad Q boosted in the low frequency

band centered at 100Hz and a narrow Q boosted at 4 kHz. In this way you are accentuating the best and

downplaying everything else this particular kick drum has to offer.