What Does An Overdrive Pedal Actually Do?
An overdrive pedal is one of the first things a metal guitarist gets told they should buy.
If the world of pedals and overdrives is new to you, you may not understand exactly why this is so common, and what the benefits are.
You may be like me, who heard Yngwie Malmsteen used an Ibanez TS9, bought one, then immediately returned it because you sounded like a blues guitarist.
(I’m not kidding, that really happened.)
We’re going to break down what an overdrive does and why it holds such a place of importance on any metalhead’s pedalboard.
WHAT IS IT?
Overdrive is a very mild form of distortion. Distortion is used to describe the sound you get from adding gain to the point where a signal “clips” resulting in that aggressive, “fuzzy” or “gritty” guitar sound.
An overdrive pedal usually has very little to offer in the way of distortion and can’t take your from a clean sound to a screaming metal tone, but instead provide a much more subtle effect. It uses “soft” clipping as opposed to “hard” clipping.
The “overdrive pedal” as we know it today was actually inspired by an effect that occurred when a tube guitar amplifier was pushed to its limits, “overdriving” the amplifier and changing the sound.
In metal, an overdrive is oftne used in front of an already distorted high-gain amplifier, as opposed ot using it on the clean channel for your main source of distortion.
WHAT DOES IT SOUND LIKE?
The sound of an overdrive pedal can be characterized as giving a little bit “more” to the tone. In the scenario of boosting an already distorted amplifier, it tends to tighten it up and add a bit of grit and sustain.
There are two main functions of an overdrive that are responsible for its iconic sound: the first being cutting lows, and the second being boosting mids.
An overdrive pedal has a high pass filter, which means it lets high frequencies “pass-through” and filters out low ones.
This high pass filter is what is responsible for the “tightening” effect we notice when used in front of a high gain amplifier. It removes some of the low end (roughly from about 100Hz down, depending on the model) gradually to take a boomy amp to a more focused one.
These days manufacturer’s have different levels of high pass filtering in their pedals, with some even going as far as making it fully adjustable to tailor your tone precisely.
The second function is a boost in mids. This is partly due to the pedal’s design, but also comes partly as a byproduct of removing the low end.
This mid-heavy contribution has several benefits:
1) The guitar is a midrange instrument, meaning that’s where it should fit sonically in a band mix. A bass would fit in the low end, cymbals fill the high end, and guitars sit in the middle. So, midrange boost can help your guitar stand out.
2) In a dense mix you can use an overdrive to provide not just a volume boost but an EQ-based boost, by adding more mids to a particular moment – such as a guitar solo – you help that instrument stand out during a section where it needs to be the focus. In short, it’s great for solos.
3) With a high gain, heavy metal guitar tone it can change the quality of the midrange frequencies, making them thicker, more aggressive, or even smoother. It can add that final polish to your tone, that last 5% to refine an amplifier.
In metal music, an overdrive is typically used with little to no gain added using the gain knob, but instead, they used the volume knob to control how hard we’re hitting our amplifier and how much we are “overdriving” it. It can control the overall “amount” of the effect.
A typical starting point is to set the gain knob to 0 and the volume knob all the way to 10 with the tone knob somewhere in the middle. This is by far the most common setup for a metal guitarist’s signal chain, but you should always tweak your settings to find what’s right not only for you and your ears but that particular overdrive pedal.
Metal can be such a sonically dense and technical wall of sound, that by focusing our guitar tone we can improve the clarity of our mix overall by removing unnecessary low end and tightening up our amps, making them more responsive.
That’s part of the joy of overdrives too, they can change the way your amp FEELS, how it reacts to the way you pick the strings.
ARE THEY ALL THE SAME?
Each overdrive has its own “sound” to it.
These different sounds depend on a number of factors, including what parts are used to “clip” the signal (LED’s, silicone diodes, germanium diodes etc.), what chip is used, whether a pedal uses symmetrical or asymmetrical clipping, how the high pass filter has been tailored, what extra knobs have been added, and so on.
While most overdrives have 3 controls – tone, gain, and volume – other pedals like the Precision Drive offer controls such as multiple clipping options, 3-band EQs, brightness controls and more. A pedal with lots of tonal features can become a Swiss army knife of tone!
DO I NEED ONE?
If you’re already perfectly happy with your tone, then probably not. However, there’s a certain quality that comes from using an overdrive, it simply takes what your amplifier is doing and refines it. It just adds “more.”
If you’ve never used one before I highly suggest trying one out at your local music store or borrowing one from a friend so you can see how it can enhance your current setup.
While it’s not mandatory, there is a reason that it has become such an essential on metal guitarists’ pedalboards around the world.