When choosing effect pedals to enhance your guitar tone one of the most confounding things to come up against as a beginner is the difference between overdrive, distortion and fuzz. The terms are often used interchangeably, but they have subtle differences in meaning.
Overdrive effects are the mildest of the three, producing warmer overtones at quieter volumes and harsher distortion as volume or gain is increased. A distortion effect produces approximately the same amount of distortion at any volume, and its sound alterations are much more pronounced and intense. A fuzz box alters an audio signal until it is nearly a square wave and adds complex overtones. Described this way, the lines between them seem fairly clear. But for fledgling guitarists, their actual application can still seem quite murky. Add to that the fact one company’s distortion can sometimes be labeled as another’s overdrive, and what you get is a recipe for some serious head scratching. Making Music huddled up with HG (Harris) Thor from the HG Thor Guitar Lab, a guitarist of 44 years with experience in guitar, bass and amp customization, who in turn got some input from Brian Wampler of Wampler Pedals, to help shed some light on an otherwise distorted subject.
“Pedals are generally made using solid state devices like transistors, diodes and op amps (operational amplifiers or “chips”),”says HG. “Predating solid state designs were tube (valve) amplifiers with preamp tubes and power section tubes. They were designed to sound clean, so players wanting distortion required some kind of boost to overdrive the amp.” This is why overdrive pedals are often confused with distortion pedals—because Overdrive does shape your tone by distorting it. And the confusion is justifiable because, quite frankly, if you crank the average overdrive to the max it will also add an element of self-generated distortion. But it lacks the necessary circuitry to be a true distortion pedal. Overdrive is often described as smooth and natural sounding, while distortion pedals add a crunchier, grittier sound. Brian Wampler of Wampler Pedals describes them as: “Basically, overdrive, distortion and fuzz are all just references to how hard the signal is clipping. Overdrive will be soft clipping, Distortion will be harder clipping, and Fuzz will be square wave (very hard clipping).”
There is an enhanced version of the overdrive pedal with circuitry in it that will actually provide mild amounts of distortion—it’s called “clipping” circuitry. Clipping is a non-linear process that produces frequencies not originally present in the audio signal. The combination of this mild clipping and the boost that an overdrive normally provides really makes a tube amp sing. You’d primarily use it to boost a solo or enhance a particular guitar part.
A true distortion pedal typically features a circuit that is designed to generate a greater amount of internal distortion and often has additional stages to provide a boost in output level. “One could equate this with distortion that would occur in the preamp tubes of a high gain tube amp,” says HG. Again, a distortion effect produces approximately the same amount of distortion at any volume, which is not true of an overdrive pedal. Basic distortion boxes can be built around a simple network of transistors, op amps and clipping diodes, to both boost the signal and alter the waveform.
Generally, fuzz pedals are not meant to simulate an overdriven or distorted amp. Fuzz is a harder, harsher and buzzier distortion than overdrive, and usually considered harder and harsher than distortion itself. To really comprehend what a fuzz pedal sounds like, listen to the second half of the solo in Jimi Hendrix’s “Purple Haze.”
Overdrive
Adding a preset amount of gain with just a single control is a great way to boost your signal for lead work.
Enhanced Overdrive
“In this pedal, the “Overdrive” control increases distortion within the pedal itself,” clarifies HG. “This famous pedal is more a self-contained Distortion than it is a volume boost, and has been used by many famous players.”
Distortion
Brian Wampler says Plexitortion, “provides a tighter distortion, more like pre-amp tube distortion where the Pinnacle is a bit looser, more like power tube distortion.” This type of effect was made famous by such players as Steve Vai and Joe Satriani.
Fuzz
Distortion created by 2 transistors overdriven resulting in square wave distortion. A favorite of Eric Johnson.
