Second only to perhaps your amp and pickups, EQ and overdrive pedals have the power to impact your guitar/bass tone in dramatic ways. Here’s what they do and how you can put them to use in your rig.
EQ Pedals
EQ pedals are great tools for carving out a particular swath of sonic territory, boosting frequencies into an amp (thus clipping them harder), or minimizing problem frequencies (honk, quack, bite, or mud) in your instrument. Many EQ pedals are equipped with an onboard level control, which doubles their usefulness as a clean boost when the time is right. Which type is right for you depends on your needs.
Types of Pedal EQs
Graphic EQs
Graphic EQs, available in knob and slider styles, rule the roost for global shaping and sweetening. Slider parametrics offer greater visual feedback and control than their simpler knob siblings, making it fast and easy to “draw in” a midrange contour or bass boost. In pedal form, graphic EQs are typically available in 3- to 10-band variations; the more bands, the greater control you have. While graphic EQs are great for shaping, their fixed frequencies are less effective at fine-tuning.
Parametric EQs
For more surgical applications — neutralizing a nasty midrange frequency or accentuating a particular low-end resonance — you’ll want a parametric EQ. Unlike fixed-band graphic EQs, parametric EQs allow you to sweep through a range of frequencies to home in on a particular band. Whereas a graphic EQ may only give you frequency centers (bands) of 100Hz and 200Hz, parametric EQs can target frequencies between those bands (150Hz, for example). Fully parametric EQs, as opposed to semi-parametric EQs, will let you control how tight or how wide the bandwidth (Q) is as well, for tighter cuts and gentler boosts.
Specialty EQs
Blurring the lines between traditional parametric and graphic EQs are specialty guitar EQ pedals, such as the EHX Screaming Bird and JHS Haunting Mids. These target a particular range of the frequency spectrum to, for instance, push the top end of an overdriven amp or manipulate the midrange character of an overdrive pedal.
Overdrive Pedals
Characteristics
Hair. Gristle. Guts. Guitarists have names for overdrive characteristics that would make a non-player’s skin crawl. Let’s look at how these terms apply to the defining characteristics of an overdrive circuit.
Gain: the range and flavor of clipping imparted by the overdrive circuit; also known as drive, breakup, and distortion. Clipping in an overdrive pedal can be generated by op-amps (ICs), discrete transistors, clipping diodes, or vacuum tubes — all of which can contribute a particular flavor when placed strategically in a circuit.
Output: even at low gain settings, an overdrive pedal is an effective tool for front-loading the preamp stage of your amp, resulting in greater breakup and enhanced distortion characteristics.
Treble/presence: overdrive pedals tend to accentuate treble response as clipping is introduced. This treble boost ranges widely in character from pedal to pedal, from the more ethereal (air, harmonics, presence) to the more attention commanding (grind, gristle, fizz, bite, etc.).
Midrange character: a hallmark of any overdrive circuit is its midrange character. The classic TS808 Tubescreamer, for example, is marked by a forward mid-bump, while the infamous MT-2 Metal Zone is regarded for its scooped, smiley-face contour.
Bass response: big, tight bass is essential for modern rock and metal guitar. Traditional overdrive circuits tend to roll off low end and accentuate midrange and treble frequencies. But specialized bass guitar overdrives and higher-gain modern pedals, exemplified by the Friedman BE-OD, are built to enhance bass and give your overdrive channel bone-crushing authority.
Harmonics: since a typical 6-string’s fundamentals max out at just over 1kHz, its harmonics, which extend all the way up to 20kHz and beyond, account for nearly half its tonal character in terms of octaves. Overdrive pedals tend to clip lower frequencies (fundamentals) first, which accentuates even-order harmonics by comparison.
Touch dynamics: this is not typically an additive quality, meaning an overdrive will rarely add dynamic response to a clean signal, but it is an important factor in choosing an overdrive. A Klon and its derivatives, for example, tend to be much more responsive to playing dynamics and guitar volume than, say, a TurboRat.
How to set your overdrive pedal
Even the perfect pedal in untrained hands can yield undesirable results. Experimentation, along with a healthy knowledge of pedal setting, will go a long way in helping you achieve the tone of your dreams. Here’s a good way to dial in that new overdrive pedal on your board.
- Start by setting the gain (drive) as low as it will go
- Strike an open string (guitar: low E; bass: A) repeatedly and cycle the pedal on and off
- Set the pedal’s level and tone controls so that your wet and dry signals sound roughly the same in terms of output and tonality. This will be your baseline.
- Slowly sweep the level control up and down. Note the interaction with your amp. Is there a setting where the amp speaks, or resonates, in a particularly pleasing way? Note this setting. This is your sweet spot. Return the level control to your baseline.
- Slowly sweep the gain control up and down. Note different drive and sustain characteristics at different settings — does it sound smooth or punchy? Aggressive or sweet? Next, observe how much gain the pedal has to offer fully open. It’s helpful at this stage to decrease the pedal’s level and tone controls to maintain your baseline as output and brightness naturally increase.
- Find the amount of gain you prefer (this will be largely a personal choice), and set the output level to achieve the output sweet spot from Step 4. Use your ears — with the added gain, your sweet spot will likely fall in a different spot on the level control.
- Finally, adjust your tone control(s) to taste. This is another personal choice and will take some experimentation. If you alternate between clean and drive channels, you’ll typically want a tone that is not too dissimilar in terms of tonal character — neither too thin or too beefy by comparison.
We hope this article has helped you better understand the roles of EQ and overdrive pedals on your board. Don’t hesitate to reach out to your Sweetwater Sales Engineer at (800) 222-4700 to learn more about the many drive and EQ pedals we offer.