A. Signal-Based Terms
Clipping is a form of distortion where the amplitude of a signal is too powerful for the medium transmitting it. This could be a cable, a vacuum tube, or a digital device's internal resolution. Looking at the resulting waveform, it appears that the peaks of the signal are "clipped" off. Different devices clip differently, and while some forms of clipping are desirable (most often tube clipping), others are usually undesirable (cables or digital clipping).
Any transformation of a signal can technically be called distortion. For guitars, it usually refers to a specific, desired transformation - the sound of vacuum tube clipping, even if these are emulations by solid state analog devices like stomp boxes, or created by digital algorithms in modelers.
A signal is the physical embodiment of information communicated from one device to another. In guitar terminology, this usually means the strings inducing electric potentials in guitar pickups, which are passed on through cables into amplifiers, then into speakers where it is converted to sound and sent to the audience's ears. The signal is the message desired to be communicated. Hum, noise, and other interference are generally not considered the signal. In fact, they are considered to degrade the signal.
Noise is essentially randomness in the signal. Being chaotic, noise transmits little information, other than that it is noise. Whereas a signal indicates timbre, pitch, and harmony, noise does not convey any of these qualities. The timbre of a guitar can change based on playing style, string gauge, pickups, woods, build quality...noise is always noise.
v. Signal-to-Noise Ratio (SNR)
A measure of the noticeability of the signal compared to the noticeability of noise. The higher the ratio, the "cleaner" and more "high fidelity" the sound.
Electrical resistance to an alternating current. Direct
current circuits amount of current is limited by the voltage of the
power source and the resistance of the circuit. Similarly, impedance
determines the amount of current flowing in an alternating current.
Where the two concepts are fundamentally different is that impedance is
variable depending on frequency. Normally, devices will have a resonant frequency where the impedance is least around a certain frequency, allowing a stronger flow of current at that frequency, while frequencies above the resonant frequency has increasingly high impedance and roll-off high frequencies.
vii. Signal Chain
A signal chain is simply the ordered list of each device that affects the signal from its point of origin (the guitarist/guitar) until it is turned into sound waves. Typically displayed as text with arrows between each piece of the chain, showing the direction of the signal as it is transformed. For example:
Ibanez guitar with Dimarzio Pickups > Ibanez Tube Screamer stomp box > MXR Flanger > Marshall JCM-800 amplifier > Marshall 1968 4x12 cab with Celestion T-75 speakers
Refers to a single, independent signal. Most simple guitar signal chains are mono - the guitar is generating a single signal from a single pickup (or two pickups wired together), going through a single cable into a single amplifier input, into a single speaker cabinet. Any device that has a single input and output is said to be mono.
Stereo refers to two independent signals operating in parallel. Most home stereos systems are called stereos because they output two independent signals through a pair of speakers. And these are often arranged to the left and right of the listener. In guitar terms, the stereo signals originate from a single point - the guitar, even if the guitar outputs from two independent pickups, such as a piezo and a magnetic (or 2 independent magnetics). Also, the signals are often sent to the same or similar devices designed to process both signals. Thus, the two signals are often referred to as a single stereo signal. Most often, stereo signals don't come into play until an amplifier's fx loop, where a mono signal is sent to a stereo fx unit where it is split, processed differently for each signal and output as a stereo signal. The amp then will amplify each signal independently and send them to two different cabs. Or a mono single is split and sent to two amps. Or as previously mentioned the guitar itself outputs stereo from 2 different pickups.
For a stereo signal, one of the two independent signals is often called a field. So every stereo signal has two fields, usually called a left and right field.
In reference to a stereo signal, balance refers to the relative volume of the left vs. right fields. Turning the balance all the way to the left would completely mute the right field.
Pan refers to the proportion of how a signal is routed into the left or right field of a stereo signal. For example, if you have mono guitar signal in a mixer or DAW, panning center means the signal is equally audible in both the left and right fields. Panning full left would mean the signal is just as loud in the left field as when panned center but is muted in the right field. Occasionally, a pan control will be applied to a stereo input signal, and in this case, the center setting will retain the original balance, but panning left or right will push both fields into either the left or right field.
Notice the difference between balance and pan. Balance operates by adjusting the relative volume of each field of a stereo signal. Panning "pushes" a signal into one field or the other or both.
B. EQ-Based Terms
i. Frequency Response
Any signal can be broken down into an infinite
number of amplitude levels for an infinite number of frequencies. Many
devices will tend not to equally affect all frequencies - this affect on
the signal can be called its frequency response. Speakers often have
unique responses, and will often display a frequency response graph - a
visual representation of how it affects frequencies input into it. All
devices have their own responses, but many (most obviously amplifiers)
include EQ controls to vary this.
Refers to the technique of altering the amplitude of
certain frequency ranges of a signal. Despite being called
"equalization", EQ controls are often purposefully used to create a frequency
response that features unequal amplitudes across the frequency spectrum.
All analog EQ's work by reducing the amplitude of some frequencies vs. others. Thus, they are commonly called filters as they "remove" some frequencies but not others. EQ's that claim to boost some frequencies are actually filtering out all the other frequencies, then amplifying the entire signal.
A filter designed to reduce frequencies around a specific target frequency.
Basically the opposite of a band-stop - reduces all frequencies except for those around a specific target frequency.
A low-pass filter allows low frequencies to pass, but filters out frequencies above a certain point. It can be rather gradual so that as frequencies get higher and higher they get slightly softer and softer until they are inaudible, or it can be rather abrupt, where frequencies lower than the cutoff frequency are nearly completely unaffected, but frequencies above the cutoff are completely inaudible. A high-pass filter is the reverse - high frequencies are allowed to pass but low frequencies are filtered more and more powerfully the lower the frequency.
A Shelf is similar to a low-pass or high-pass filter; however, instead of the signal getting softer and softer as the frequencies get higher and higher (or lower and lower), the effect only occurs over a range of frequencies. Any frequencies higher (or lower) than that point are not reduced any further. The effect's result on the frequency spectrum looks like two parallel shelves. IE: ---- becomes --__. Often the filtered freqeuncies are called the low shelf and the unfiltered the high shelf.
Just another term for band-pass or band-stop filters. Their resulting effect on the frequency spectrum looks similar to a mountain peak or a valley.
This is the "width" or steepness of a filter's effect on the frequency spectrum. A high Q on a band-stop indicates a very narrow range of affected frequencies, often used to "notch" out a small offensive frequency. Whereas a low Q may affect nearly the entire audible frequency spectrum. For a high-pass or low-pass filter, a high Q will be a steep, abrupt drop-off in frequencies at the cutoff frequency, while a low Q is a more gradual roll-off. Similar a Shelf with a low Q will have a gradual, smooth transition from the high shelf to the low shelf, while a high Q implies a dramatic, steep jump.
The cutoff frequency on a low/high pass or shelf EQ is the frequency where the EQ acheives 3 db signal reduction - basically the frequency when you start to notice the effect.
xi. Parametric EQ
A parametric EQ is a band-pass/band-stop filter with adjustable cutoff frequency, Q, and gain (or mix).
xii. Graphic EQ
A graphic EQ consists of a number of band-pass/band-stop filters at fixed frequencies throughout the frequencies spectrum to provide a near continuous effect across across the spectrum, usually controlled by vertical sliders to approximate the visual appearance of the filters' effect on the spectrum.
xiii. Notch EQ
Usually has multiple bands, but is designed to provide very high Q band-stop filters to create narrow "notches" in the frequency response to filter out offensive frequencies - can be useful to remove an unwanted fixed frequency fizz or hiss or hum.
C. Tone-Based Terms
Musicians often use this term to cover any feature the sound of
any particular instrument or device contributes to. Some common usages
refer to frequency balance - how much high frequencies are present
compared to lower frequencies or vice versa...or a particular
characteristic of the frequency range (ex. dark tone, bright tone, midsy
tone, scooped tone, etc.). Another usage describes the fidelity of the
signal, often referring to tone as though it is a quantified amount.
For example, someone might call some device a tone-suck, which means the
device increased the noise relative to the signal. Or he might say some
device has a huge tone, meaning the output is high-fidelity - low noise
and low unwanted distortion. It can also refer to the amount of
distortion the device produces. While those are the typical usages of
the term, it can even refer to more quirky features, like being swirly,
or shimmering, or ambiant.
The Pod tends to get a lot of complaints about "fizz", which is
high-frequency noise, taking its name from the sound you get after
pouring a carbonated soda into a glass. It also sounds similar to
saying, "shhh" or the background noise you hear while flying on an
airplane. It becomes prominent from around 3kHZ and up. Fizz is not
limited to the Pod, but appears in some form in all modelers, and many
analog devices such as microphones. There is no surefire way to
eliminate it in the Pod, but I find the best benefits are from careful
cab/mic choices and narrow Parametric EQ reductions. It tends to effect
high-gain tones more than others due to their extended emphasis on
If fizz is "sshhh", buzz is "zzzzz". It is lower frequency than
fizz, but still a feature of the upper end of the frequency spectrum.
It's most common representation is a sawtooth wave, also called a
buzzsaw. While a triangle, sine, or square wave could be considered
"smooth", a sawtooth or similar wave featuring buzz is "rough" or
grinding, like there's a little distortion in the tone.
This gets its name because it sounds similar to stones or
metal being grinded. Somewhere in between crunch and buzz - a
characteristic of a rather raucous distortion. Can sound kind of
"throaty", like a sustained hardcore/metalcore yell.
Similar to buzz but lower in frequency, like trying to say,
"kkkkkk". Most distorted guitar tones tend to have at least a little
crunch to them. This becomes confusing because amplifiers often label
their channels as "clean", "crunch", and "lead". Clean and Lead
channels can have crunchy aspects to them. A crunch channel is often
marked a mild distortion that is focused on being crunchy in nature, as
opposed to fuzzy or grinding. Similarly, sometimes a crunchy tone is
assisted by being dry, so that the crunch sound is more easily heard.
While squishy and crunchy are somewhat in contention, a tone can be both
squishy and crunchy at the same time. Generally, however, getting the
maximum amount of squish means sacrificing some crunch and vice versa.
Crunch tones are often acheived by using very balanced or slightly
scooped tones into a distortion stage.
Refers to the amount of low-end in the tone. I
associate chunk with the ultra-low-end around 100 HZ and punch more
around 240 HZ, but many people use the terms interchangeably. Depending
on the genre of music and the target guitar tone, it may refer to
slightly different things. For example, in heavy metal, chunk is often
in reference to how much squishy low end a palm mute generated, whereas
for genres that have only mild distortion on guitars, punch might refer
low-end percussiveness on the attack of a note or chord.
A fuzzy tone is a distorted tone where most of the break-up is
occurring in the lower frequencies. Fuzzy tones are known for an
unfocused or loose bottom end and a buzzy high end. This can leave it
difficult to discern the pitch of fast passages in lower registers, and
thus fuzz is often avoided in metal. Additionally, simultaneous notes
on different strings tend to "fight" each other for audible dominance.
Chords tend to get extremely distorted and difficult to discern. Fuzz
is often used in small amounts or in lead settings, although some
alternative, indie, and post-rock musicians tend to enjoy the
out-of-control tone it can generate at high gain levels.
This term incorporates multiple facets of the tone. In the most
general sense, it is a tone that is somewhat discomforting to hear for
long stretches at a time, although a full mix with a cold guitar tone
isn't necessarily difficult to listen to. It can refer to a dry tone
(see "dry" below), or a scooped tone, but even if a tone has plenty of
mids, it can still be considered cold. Generally the area of midrange
in question is around 350 - 800 HZ. It can also refer to a bright tone
(see "bright" below), as well as an overly crunchy or a grinding tone
(see crunchy and grinding below). It can also refer to a tone that
focuses intensely in one frequency range.
Opposite of a cold tone - easy to listen to, with most
frequencies in balance, and a healthy dose of "warm" frequencies from
350-800 HZ. Likely to have some resonance or reverb or delay to add at
least some ambiance.
This actually refers to something different than the warm/cold
dichotomy above. In reference to signal levels, a hot signal is used to
describe a signal that is exceeding or nearly exceeds its maximum level
before clipping/distorting. In reference to tone, this translates into
the amount of distortion applied to the tone. A "hot" tone has lots of
distortion. It can be used to express negative or positive connotations
towards the level of distortion. For example, one may say the tone is
"too hot", or one may say, "Man, that tone is hot!"
This has two different contexts. One is used to describe the
ambiance of the tone, which factors in resonance, reverb, or delay. A
dry tone would have very little ambiance. The other context is used to
describe how much effects are mixed into the tone. This context is
often used when describing a Wet/Dry or Wet/Dry/Wet (W/DW) setup, where
the main guitar signal is split in two (or three), with one side having
no effects and the others having effects, such as modulation, reverb,
delay, pitch shifting, etc. applied. Often the individual effects will
have their maximum or otherwise extremely high mix settings used, and
this "wet" signal(s) is mixed against the "dry" (no effects) signal to
find the right balance of how "wet" the tone should be. The greater the
balance of the "wet" signal(s) vs. the "dry" signal, the "wetter" the
tone is said to be.
Opposite of dry. See "dry".
Has two somewhat synonomous meanings. One describes a tone with
greater emphasis on lower frequencies vs. higher frequencies as judged
from the frequency response heard. The other refers to the nature of
the distortion resulting from a dark signal being fed into a distortion
stage. The distortion will usually be fuzzy and be quite broken up.
Opposite of dark. In reference to distortion, a bright
distortion will often sound crunchy or sizzling (see "crunchy" and
"sizzle"), perhaps even grinding (see "grinding"). The low-end will be
"tight" and have more focus - no fuzzyness.
Generally the opposite of buzz. Sounds more like "oooo" than
"zzzz". Also can refer to a lack of crackle in the tone/signal (see
This refers to the nature of the tone's distortion,
mainly in reference to the attack and sustain of palm mutes. A squishy
tone has a weak attack and a long sustain - the opposite of a percussive
sound. Overall, the tone sounds more like a synth than a drum. The
squishy characterstics are all present in unmuted playing - while there
may be much more attack there, the tone is still very compressed and
sustains relatively long. Two factors that contribute to a squishy tone
are plenty of distortion and a mid-range focus to the signal being
Term used to describe squishy palm mutes with a strong presence
focus that makes them stand out. It is evident when playing muted power
chords, particularly when using 4 or more notes.
Describes a tone that is not smooth at all, but not
necessarily buzzy. Similar to cracky, but whereas crackly is marked by
a cracking/tearing type sound in the tone, splatty is marked more by
random drop-outs to the tone and high-pitched squeals. It generally
occurs by feeding an extremetly bright signal to a heavily distorted
A noisy cracking or tearing type sound in the tone, noted by a
seemingly random (irregular) appearance in the signal. Often caused by
bad connections due to worn out cables or turning bad guitar pots.
Rarely caused by settings, but can appear due to distorting multiple
gain stages in succession to a high degree.
Basically just a grinding distortion but the "clanking"
nature is emphasized when the tone is more percussive than squishy.
This refers to a tone that is so extremely bright, it hurts
to listen to. It is said to be like driving an ice-pick into your ears.
It can be due to high amounts of high frequencies that are normally
very low volume compared to other frequencies in guitars - such as
anything over 5-8 kHZ. But it can also be due to a peak frequency lower
than this (such as 3kHZ) that is simply extremely loud.
A harsh tone is any tone that is difficult to listen to at high volumes or for long periods of time, generally due to an overly bright frequency response or crackly, buzzy, or grinding nature of distortion.
Generally a tone that is too dark or has distortion on the
low-end, causing it lose focus and tightness, similar to fuzz.
Basically fuzz applied just to the low-end. Almost always used in a
negative context - unwanted mud.
Usually means the tone is too bright, but isn't just related to
the frequency response. It can also mean the tone is too dry or the
distortion isn't squishy or warm or punchy enough. The term relates to
the association of thinner strings or objects having less mass and
producing less momentum, resonance, and lower frequencies.
Opposite of "thin" and often used in a positive context. You
are more likely to hear "too dark" than "too thick".
High-gain typically refers to an amplifier designed to add large amounts of distortion into the signal. Early guitar amps had no "Drive" or "Gain" control, only a master volume control. After amp manufacturers realized many players were turning up their amps as loud as possible to purposefully induce distortion, they incorporated this ability into their pre-amp circuits, where the player had more control over the level of distortion without having to make his amp deafeningly loud. Technically, any amp with a pre-amp "Drive" or "Gain" control is considered a "high-gain" amplifier, although different amps will provide different characteristics and levels of distortion.