Mixing – Page 17 – My New Microphone

Equalization (EQ) is one of the most important and commonly used processes in audio. It makes perfect sense, then, that the market would produce EQ pedals for our guitars and bass guitars. What are EQ pedals, and how do they work? EQ pedals adjust the relative amplitudes of the frequencies within a guitar or bass signal. An EQ pedal, when set correctly, helps to balance the sound of the guitar/bass by boosting and/or cutting certain frequency ranges (bands), improving the signal's sound/character within a mix and by itself. In this article, we’ll discuss EQ pedals in much more detail, covering the inner workings of equalizers and how they affect guitar and bass guitar signals. I’ll share a few EQ pedals throughout the article and offer some tips on how to get the most out of your EQ pedal (if you choose to use one). Related My New Microphone articles:• The Ultimate Effects Pedal/Stompbox Buyer’s Guide• Top 11 Best Guitar/Bass Effects Pedal Brands To Know & Use• Top 12 Best EQ Pedals For Guitar & Bass• Complete Guide To Audio Equalization & EQ Hardware/Software• Top 11 Best EQ/Equalization Tips For Mixing (Overall) Table Of Contents What Is EQ/Equalization?Controls & Filter Types Found In EQHigh-Shelf EQLow-Shelf EQBell EQHigh-Pass FilterLow-Pass FilterBand-Pass FilterBand-Reject FilterAll-Pass FilterA List Of The Different Types Of EqualizersFixed-Frequency EQGraphic EQParametric EQSemi-Parametric EQDynamic EQWhat Is An EQ Pedal?Types Of EQ PedalsGraphic EQ PedalsParametric EQ PedalsSemi-Parametric EQ PedalsEffects Pedals With EQ CircuitsOther Effects That Modulate EQAre EQ Pedals Necessary?Tips On Using An EQ PedalWhere Should EQ Pedals Go In The Signal Chain?Related Questions What Is EQ/Equalization? EQ (equalization) is the process of adjusting the balance between frequencies within an electronic signal. In terms of audio, EQ typically works on the audible frequency range between 20 Hz and 20,000 Hz though some EQ units are capable of affecting frequencies beyond this audible range. By adjusting the balance between audible frequencies, EQ can raise the level of (boost) some frequencies while lowering the level of (cutting) some other frequencies. It may simultaneously leave other frequencies untouched while completely removing other frequencies from the signal altogether. Another way of looking at EQ is as a frequency-specific volume/gain control. We can turn up some frequencies while turning others down. The frequencies affected by EQ are typically referred to a "bands". A band of frequencies is essentially a range of frequencies with a low point and a high point. The frequency spectrum of audio/sound waves is continuous, and so EQ doesn't only affect a single specified discrete frequency. EQ is an invaluable tool for audio mixing. Equalization and compression are the two most commonly-used tools in audio mixing and mastering. Why is EQ so important? There are several reasons, including: EQ can correct the response of a less-than-ideal instrument pickup or other transducer (microphone, headphone, loudspeaker).EQ can eliminate unwanted noise and other "problem frequencies" from a signal.EQ can be tuned to "tune the room", thereby reducing standing waves in an acoustic environment and mitigate the risk of feedback in an audio/sound system.EQ can help place an element more appropriately in a mix.EQ can adjust the timbre/tone of an instrument/source to improve its sonic character. As we can see from the list above, EQ is a very powerful tool. It's critical that audio engineers understand EQ thoroughly, and it's equally important for guitarists, bassists, and all musicians to understand, at the very least, the basics of this tool. If EQ is used to affect the frequency response of an instrument to improve its sonic character and make it fit better in a mix, then surely guitars and bass guitars could benefit from having their own EQ inline with a pedal. That's what this article is all about! Back to the table of contents. Controls & Filter Types Found In EQ So we know that EQ works to balance/adjust the relative amplitudes of frequency bands within the audible spectrum of an audio signal. Now let's dive deeper into how it does so. The first thing to note is that EQ, like audio signals themselves, can be analog or digital. EQ units come in hardware and software packages. Of course, as the title of this article would suggest, EQ hardware does come in pedal format. The next thing to note is that there are several types of EQ to be aware of. We'll get to these shortly. This section will focus on how EQ works by looking at the controls and filters that alter the frequency-specific amplitude of the signal. I'll separate shelf and bell EQs from the filter EQ controls to distinguish between the two: shelf and bell EQs can boost or cut their ranges while filters generally remove frequency bands altogether. Shelf & Bell EQs Shelf and bell EQs allow us to boost (increase relative amplitude) or cut (decrease relative amplitude) different frequency bands of the signal. Let's discuss each quickly and have a look at a few illustrations to help explain. High-shelf EQLow-shelf EQBell EQ High-Shelf EQ Shelf EQ is done with a first-order filter, meaning it can alter the response of frequencies above (or below) a point. In the case of a high-shelf EQ, we're affecting the amplitude above a certain setpoint. First-order filters can have a slope of up to 6 dB per octave in the transition region. In the case of a shelf filter, the transition region is the frequency range between where the EQ begins altering the amplitude and the point at which the appropriate amplitude change is achieved. So a high-shelf filter is used to increase (boost) or decrease (cut) the amplitude of a signal above a certain set frequency. When it comes to guitar/bass pedals, treble control is typically a high-shelf EQ. In the illustrations below, you'll see a visual representation of a high-shelf boost and high-shelf cut, respectively. Notice the transition region (the EQ line doesn't immediately jump from one amplitude to another. Low-Shelf EQ A low-shelf EQ is another shelf-type EQ, meaning it's a first-order filter. This time, the EQ is focused on adjusting the relative amplitude of frequencies below a set point. So a low-shelf filter is used to increase (boost) or decrease (cut) the amplitude of a signal below a certain set frequency. When it comes to guitar/bass pedals, bass control is typically a low-shelf EQ. In the illustrations below, you'll see a visual representation of a low-shelf boost and high-shelf cut, respectively. To learn more about high-shelf and low-shelf filters, check out my article Audio Shelving EQ: What Are Low Shelf & High Shelf Filters? Bell EQ A bell EQ is perhaps the most commonly-used control in dedicated EQ units. The bell filter, like the shelf filters, is capable of boosting or cutting frequency-specific amplitudes. However, unlike the aforementioned shelves, the bell EQ tool is a second-order filter. Second-order filters are capable of producing resonance (boost in EQ) or anti-resonance (cut in EQ) around a specified frequency. Bell-type EQ takes advantage of this. This is unlike first-order filters, which can only affect frequencies above or below a set point. Bell EQ affects the amplitude at (and around) a set point. This can be visualized in the following illustrations of a bell boost and cut, respectively: Three factors define the response of a bell EQ: FrequencyQ (quality factor)Gain Frequency refers to the centre point of the bell EQ tool. This is the frequency at which the boost or cut will be at its maximum. This is measured in Hertz (Hz) The Q (quality factor) is dimensionless and refers to how narrow/steep or wide/gentle the boost or cut will be. A higher Q will produce a narrow band in which a smaller range of frequencies is affected. Gain is measured in decibels (dB) and refers to the relative change in amplitude caused by the bell EQ. Boosts will have positive gain, while cuts will have negative gain. Note that "gain" here is only relative to the 0 dB "starting point" of the overall EQ. If you're at all confused about decibels, my article What Are Decibels? The Ultimate dB Guide For Audio & Sound has all the information you'll need! Here is a picture to help illustrate these parameters: Filters Now that we've discussed the tools used to boost and cut in EQ let's talk about filters. The term "filter" can be confusing. For example, I used it to describe the shelves and bell EQ tools in this article, and now I'm using it to define a whole other set of EQ tools. It doesn't make a whole lot of sense, but please bear with me. In general, when the term "EQ" is used, it refers to the boosting and cutting of various frequency bands in an audio signal. When the term "filter" is used, it generally refers to the elimination of certain frequencies from a signal. With that definition as our guidepost, let's continue. There are 5 filters we should understand before getting to the guitar and bass EQ pedals (I swear we're getting there)! They are as follows: High-pass filterLow-pass filterBand-pass filterBand-reject filterAll-pass filter High-Pass Filter The high-pass filter is perhaps the most commonly-used pass-type filter in mixing. High-pass filters "pass" the high-frequencies above their cutoff frequency while progressively attenuating frequencies below the cut-off frequency. In other words, high-pass filters remove low-frequency content from an audio signal below a defined cut-off point. To learn more about high-pass filters, check out my article Audio EQ: What Is A High-Pass Filter & How Do HPFs Work? Low-Pass Filter Low-pass filters are the opposite of high-pass filters. They "pass" the low-frequencies below their cutoff while progressively attenuating frequencies above their cutoff. In other words, low-pass filters remove high-frequency content from an audio signal above a defined cut-off point. To learn more about low-pass filters, check out my article Audio EQ: What Is A Low-Pass Filter & How Do LPFs Work? Band-Pass Filter A band-pass filter is like a combination of a low-pass and high-pass filter. It passes a band of frequencies (a defined range with a low cutoff and a high cutoff) while progressively attenuating frequencies below the low cutoff and above the high cutoff. Band-pass filters, then, pass a band of frequencies while removing those on either side. To learn more about band-pass filters, check out my article Audio EQ: What Is A Band-Pass Filter & How Do BPFs Work? Band-Reject Filter A band-reject filter, often referred to as a notch filter, is kind of like the opposite of a band-pass filter. A band-reject filter works by removing frequencies in a specified band within the overall frequency spectrum. It allows frequencies below the low cutoff point to pass along with frequencies above the high cutoff point. To learn more about band-reject/band-stop filters, check out my article Audio EQ: What Is A Band-Stop Filter & How Do BSFs Work? All-Pass Filter All-pass filters are odd. They actually do not filter any frequencies in terms of amplitude. They pass all frequencies. Rather, they work by affecting the phase of any given sinusoidal component (frequency) according to its frequency. All-pass filters, in terms of guitar and bass pedal effects, are used in phaser pedals to affect the phase of the copied signal. We'll discuss phaser pedals and their relation to EQ later in this article. Back to the table of contents. A List Of The Different Types Of Equalizers Now that we understand what EQ is and how it works, let's quickly run through the different types of EQ units (both analog and digital) available on the market. The main types of EQ are: Fixed-frequency EQGraphic EQParametric EQSemi-parametric EQDynamic EQ To learn more about all EQ types, check out my article The Complete Guide To Audio Equalization & EQ Hardware/Software. Fixed-Frequency EQ Fixed-frequency EQs are the least versatile EQ units. They're generally featured as part of another audio unit (like a guitar/bass amp or boost pedal) rather than as standalone hardware/software. To learn more about boost pedals, check out my article Guitar Pedals: Boost Vs. Overdrive Vs. Distortion Vs. Fuzz. The only control the user has with a fixed-frequency EQ is relative gain. The frequencies and Q cannot be controlled. Fixed-frequency EQs generally have 2 or 3 bands: Bass: typically a low-shelf at a fixed set frequencyMids (sometimes): typically a wide Q bell at a fixed set frequencyTreble: typically a high-shelf at a fixed set frequency These units generally do not have any visual indicators to let us know what's really going on. Graphic EQ A graphic EQ technically has fixed frequencies. It also generally won't have any Q controls. However, the layout is much different. A graphic EQ will have multiple bell-type bands across the frequency spectrum. These units will often stack the centre frequencies of their bell-type EQ curves at octave intervals. For example, a 10 band EQ could have its adjustable frequencies at the following octaves: 31.25 Hz62.5 Hz125 Hz250 Hz500 Hz1,000 Hz2,000 Hz4,000 Hz8,000 Hz16,000 Hz A 32-band Graphic EQ may have three different "octave stacks" that begin at 16 Hz (to 16,000 Hz), 20 Hz (to 20,000 Hz) and 25 Hz (to 12,500 Hz). Note that each octave increase is a doubling of frequency. Each band of a graphic EQ will have its own gain control. Adjusting a graphic EQ will give us a strong visual sense of how the overall EQ curve acts upon the signal, hence the name. For more information on graphic EQ, check out my article The Complete Guide To Graphic Equalization/EQ. Parametric EQ A parametric EQ gives us a great deal of control over the individual bands we're able to affect. We're able to sweep the frequency of a parametric EQ and set it exactly where we need it to be. We can also control the Q parameter and, of course, the amount of gain. A parametric EQ will often feature a high-pass filter and low-shelf option as well as a low-pass filter and high shelf-option, each with adjustable cutoff/set points. Some software parametric EQs allow us to change the typical bell-type bands in the centre into notch or band-pass filters as well. For more information on parametric EQ, check out my article The Complete Guide To Parametric Equalization/EQ. Semi-Parametric EQ Semi-parametric EQs are essentially parametric EQs with a few options missing. Most often, this missing functionality means no Q control. For more information on semi-parametric EQ, check out my article What Is Semi-Parametric Equalization/EQ In Audio? Dynamic EQ Dynamic EQs effectively combine EQ and compression into a single effect. These EQs are generally of the parametric variety but are not static. Rather, they are triggered by the dynamics of the input signal (much like a compressor) and react accordingly by adjusting the EQ of the signal dynamically. For more information on dynamic EQ, check out my article The Complete Guide To Dynamic Equalization/EQ. To learn more about compressor pedals, check out my article What Are Compressor Pedals (Guitar/Bass) & How Do They Work? Back to the table of contents. What Is An EQ Pedal? Okay, okay, we're finally getting to the good stuff. It's just paramount that I offer at least some information on equalization before we get to our discussion about EQ pedals. I got fairly thorough in my explanation of EQ in the earlier sections. Only a few EQ types, however, apply directly to dedicated EQ pedals. The simple answer to "what is an EQ pedal?" is as follows: an EQ unit designed into a stompbox unit, typically marketed toward guitarists and bassists. There are plenty of pedals dedicated to audio equalization and even more pedals that offer other effects that have some type of EQ built-in. They can be analog or digital, and, as we'll get to in a minute, they can be fixed-frequency, graphic, parametric or semi-parametric. So then, an EQ pedal can be put in-line in our guitar/bass rig and help to clean up our signal/tone by balancing out the frequency content. To learn about all the different types of effects pedals, check out my article The Full List & Description Of Guitar Pedal Types. Back to the table of contents. Types Of EQ Pedals Let's get into the types of EQ pedals we'll encounter on the market. We'll begin by quickly discussing the fixed-frequency EQ circuits that can be found on plenty of guitar pedals. The "tone" or "bass, mids and treble" controls we find on our pedals typically control fixed-frequency EQ circuits. I discuss these pedals in greater detail later in this article. You'll rarely see a dedicated EQ pedal (a pedal that only offers EQ) with this type of equalization circuit. The main types of dedicated EQ pedals are: Graphic EQParametric EQSemi-parametric EQ We've already been over these types of EQs; now, let's look at them within the context of guitar/bass pedals. Graphic EQ Pedals Graphic EQ pedals feature graphic EQ interfaces. These pedals have set frequency points (typically octaves apart) with amplitude sliders to adjust the boost or cut of each set frequency. The MXR M108S Ten Band EQ (link to check the price on Amazon) is a ten-band graphic EQ pedal. Each of its bands is an octave apart, starting at 31.25 Hz and ending at 16,000 Hz. It also acts as a boost pedal with volume control and make-up gain. We can visualize the EQ curve by simply looking at the MXR Ten Band EQ. MXR M108S Ten Band EQ MXR is featured in My New Microphone's Top 11 Best Guitar/Bass Effects Pedal Brands To Know & Use. The Boss GEB-7 (link to check the price on Amazon) is the bass version of the GE-7 guitar graphic equalizer. This graphic EQ has 7 bands at: 50 Hz120 Hz400 Hz500 Hz800 Hz4.5 kHz10 kHz The pedal's 7 bands fit nicely in this compact housing and control what are arguably the most important frequency points to control when EQing a bass guitar signal. Boss GEB-7 Boss is featured in the following My New Microphone articles:• Top 11 Best Guitar/Bass Effects Pedal Brands To Know & Use• Top 11 Best Guitar Amplifier Brands In The World• Top 11 Best Pedalboard Brands On The Market The Source Audio SA170 (link to check the price on Amazon) is an excellent programmable digital graphic EQ. We can get very involved with this digital pedal, saving presets and recalling them at will. Source Audio SA170 Programmable EQ Source Audio is featured in My New Microphone's Top 11 Best Guitar/Bass Effects Pedal Brands To Know & Use. The Ten-Band EQ, GEB-7 and SA170 are all featured in My New Microphone's Top 12 Best EQ Pedals For Guitar & Bass. Parametric EQ Pedals Parametric EQ pedals allow us to adjust the frequency points to be boosted or cut along with the “Q” or “sharpness” or the boost/cut. Generally, we can set one or more frequency values for each band (lows, low-mids, high-mids, highs, etc.) The Empress Effects ParaEQ (link to check the price at Reverb) is a wonderful choice if you're looking for a great parametric EQ pedal. This pedal offers 3 fully controllable bands (low, mid and hi), each with 3 selectable Q values and -15 dB to +15 dB of gain. The frequency sweep for each band is as follows: Low: 35 - 500 HzMid: 250 - 5,000 HzHigh: 1,000 - 20,000 Hz This pedal also features an input pad and a boost circuit. Empress Effects ParaEQ The Empress ParaEQ is featured in My New Microphone's Top 12 Best EQ Pedals For Guitar & Bass. Empress Effects is featured in My New Microphone's Top 11 Best Boutique Guitar/Bass Pedal Brands To Know & Use. The Orange Bax Bangeetar (link to check the price on Amazon) offers a single parametric band in its mid control along with a low-shelf (bottom) and high-shelf (top). As we'd expect, the mid-band has both frequency and Q controls along with the obvious gain control. To top things off, the Bax Bangeetar has an output gain circuit and overall volume control. Orange Bax Bangeetar Orange is featured in the following My New Microphone articles:• Top 11 Best Bass Guitar Amplifier Brands In The World• Top 11 Best Guitar Amplifier Brands In The World Semi-Parametric EQ Pedals Semi-parametric EQ pedals allow some of the same functionality of parametric EQs but not all. The typical “bass, mids and treble” adjustments can be classified as semi-parametric. The beautifully designed Tech 21 Q-Strip (link to check the price on Amazon) is a versatile semi-parametric EQ and direct-inject (DI) box. It has fixed options for both high-pass and low-pass filters along with gain-controlled low and high-shelf EQs (without frequency controls). The two mid bands (mid 1 and mid 2) are fixed-Q bell-type filters with sweepable frequencies. Mid 1 sweeps from 40 Hz to 700 Hz (the low to low-mid range)Mid 2 sweeps from 300 Hz to 6,000 Hz (the low-mid to high-mid range) Tech 21 Q-Strip The Tech 21 Q-Strip is featured in My New Microphone's Top 12 Best EQ Pedals For Guitar & Bass. Tech 21 is featured in My New Microphone's Top 11 Best Direct Inject Audio Box Brands On The Market. To wrap things up, let's talk about the awesome bass EQ pedal known as the Aguilar Tone Hammer Bass (link to check the price on Amazon). This semi-parametric EQ pedal is a little less telling. It has low and high-shelf adjustments labelled as bass and treble, respectively. It also has a single sweepable fixed-Q mid-frequency control with cutting and boosting capabilities. Aguilar Tone Hammer Bass The Aguilar Tone Hammer is featured in My New Microphone's Top 12 Best EQ Pedals For Guitar & Bass. Aguilar is featured in the following My New Microphone articles:• Top 11 Best Bass Guitar Amplifier Brands In The World• Top 8 Best Bass Guitar Pickup Brands On The Market So to recap, dedicated EQ pedals come in 3 main types, but many other pedals have EQ built into them. Of the EQ types we've discussed, the 3 that make the cut for dedicated EQ pedals are: Graphic EQParametric EQSemi-parametric EQ Of the specific filters (I'll use the term broadly), we'll find the following in dedicated EQ pedals: High-shelf EQsLow-shelf EQsBell EQsHigh-pass filtersLow-pass filters That being said, we will find the other types of filters in some other pedals. Let's now move on to those kinds of pedals! Back to the table of contents. Effects Pedals With EQ Circuits Many pedals will have some EQ capabilities even though they are not dedicated EQ pedals themselves. EQ controls come in a variety of labels. If a pedal has any of the following parameters, chances are they have some amount of control over the EQ of their output signal: BassMidTrebleToneFilterSweepQFrequency The TC Electronic Spark (link to check the price on Amazon) is a boost pedal with some EQ (bass and treble control along with fat, clean and mid settings via the toggle switch). TC Electronic Spark Booster The TC Electronic Spark Booster is featured in My New Microphone's Top 9 Best Boost/Preamp Pedals For Guitar & Bass. TC Electronic is featured in My New Microphone's Top 11 Best Guitar/Bass Effects Pedal Brands To Know & Use. The Ibanez TS9 Tube Screamer (link to check the price on Amazon) is an overdrive pedal with a tone control. Ibanez TS9 Tube Screamer The Ibanez TS9 is featured in My New Microphone's Top 10 Best Overdrive Pedals For Guitar & Bass. Ibanez is featured in the following My New Microphone articles:• Top 13 Best Bass Guitar Brands In The World• Top 13 Best Electric Guitar Brands In The World To learn more about overdrive pedals and boost pedals, check out my article Guitar Pedals: Boost Vs. Overdrive Vs. Distortion Vs. Fuzz. The Keeley Electronics Synth-1 (link to check the price on Amazon) is a fuzz-based synth pedal with a filter control. Keeley Electronics Synth-1 The Keeley Electronics Synth-1 is featured in My New Microphone's Top 10 Best Synth Pedals For Guitar & Bass. Keeley Electronics is featured in My New Microphone's Top 11 Best Boutique Guitar/Bass Pedal Brands To Know & Use. For more information on synth pedals, check out my article What Are Compressor Pedals (Guitar/Bass) & How Do They Work? Back to the table of contents. Other Effects That Modulate EQ Now that we understand EQ and how it affects audio signals, let's look at a few other effects types that utilize EQ and filters to achieve more dynamic results in the sound of guitars, basses and other instruments. Other effects that utilize and modulate EQ are: WahEnvelope FilterPhaser Wah Pedals Wah (or Wah-Wah) is a filtering effect that is common on guitars. Wah is achieved by sweeping one or more boosts in EQ up and down in frequency, generally via an expression pedal. Rocking the pedal back and forth will sweep the peak response of a frequency filter up and down, creating a spectral glide known as the “wah effect”. This sweeping is designed to mimic the human vowel sound of “wah”. The Dunlop GCB95 Cry Baby (link to check the price on Amazon) is one of the many classic “Cry Baby” wah pedals from Jim Dunlop. Dunlop GCB95 Cry Baby The Cry Baby GCB95 is featured in My New Microphone's Top 14 Best Wah Pedals For Guitar & Bass. Dunlop is featured in the following My New Microphone articles:• Top 11 Best Guitar/Bass Effects Pedal Brands To Know & Use• Top 11 Best Bass Guitar String Brands On The Market• Top 11 Best Electric Guitar String Brands On The Market For more information on wah pedals, check out my article What Are Wah-Wah Guitar Effects Pedals & How Do They Work? Envelope Filter Pedals Envelope filtering is the filtering triggered by the envelope or transients of a signal. These filters, therefore, act according to the dynamic rise and fall of a note (or chord) from the guitar or bass. In this way, an envelope filter is a dynamic EQ. The sound of an envelope filter is often described as wah-like or like a duck’s quack. Various filter types (high-pass, band-pass or low-pass) can be triggered when a guitar or bass note is struck. Envelope filters are sometimes referred to as auto-wah since they automatically trigger according to the signal dynamics. An envelope filter will then sweep the peak response of a frequency filter (high-pass, low-pass, band-pass or other) up or down, creating a spectral glide similar to the wah effect. The Electro-Harmonix Q-Tron (link to check the price on Amazon) is an awesome envelope filter pedal. Electro-Harmonix Q-Tron + The Electro-Harmonix Q-Tron+ is featured in My New Microphone's Top 13 Best Envelope Filter Pedals For Guitar & Bass. Electro-Harmonix is featured in My New Microphone's Top 11 Best Guitar/Bass Effects Pedal Brands To Know & Use. To learn more about envelope filter pedals, check out the following My New Microphone articles:• What Are Envelope Filter Effects Pedals & How Do They Work?• What Is The Auto-Wah/Envelope Filter Modulation Effect? Phaser Pedals Phasers utilize a special kind of filter called an all-pass filter. This seems confusing in terms of EQ. An all-pass filter, as the name suggests, passes all frequencies at even levels. It doesn't actually affect the EQ of this signal, or does it? An all-pass filter works by introducing a phase shift around a set frequency. So then, an all-pass filter acts as a frequency-dependent phase-shifter. Phaser pedals (and other phaser units) utilize several all-pass filters connected in series to affect the signal. For every pair of all-pass filters, there will be a resulting notch filter when the affected signal is mixed back in with the dry signal. This happens when certain frequencies of the affected signal become 180º out-of-phase with the dry/direct signal. Upon mixing the two signals, there is a significant cancellation of output at these defined frequencies. The "set frequencies" defined by the series all-pass filters can be modulated via an LFO (low-frequency oscillator) to create the sweeping effect called phaser. So then, phaser is a modulation audio effect whereby a series of peaks and troughs (boosts and cuts, respectively) are produced across the signal's frequency spectrum. These peaks and troughs in the EQ of the signal have relatively high Q values and vary over time. The MXR M101 Phase 90 (link to check the price on Amazon) is a classic phaser pedal. MXR M101 Phase 90 The MXR Phase 90 is featured in My New Microphone's Top 11 Best Phaser Pedals For Guitar & Bass. Note that flanger and chorus pedals are very similar to phaser pedals except that they use delay to alter the phase of their copied signals rather than all-pass filters arranged in series. For more information on phaser pedals, check out the following My New Microphone articles:• What Are Phaser Pedals (Guitar/Bass FX) & How Do They Work?• Complete Guide To The Phaser Audio Modulation Effect Back to the table of contents. Are EQ Pedals Necessary? Compressor pedals are by no means necessary. However, they can do wonders for our tone when used appropriately. A few benefits of a properly set-up EQ pedal include: Removing low-end noise and electromagnetic interference with high-pass filtering.Reducing problem frequencies by notching them out.Mitigating feedback by reducing standing-wave frequencies in the signal.Improving the overall mix by focusing the guitar or bass into its harmonic range.Enhancing tone by boosting "good" frequencies and cutting "bad" frequencies. Of course, no pedal is absolutely necessary. However, a good EQ pedal used correctly can be a game-changer for guitarists and bassists alike. Related article: Are Guitar Effects Pedals Necessary Or Worth It? Back to the table of contents. Tips On Using An EQ Pedal EQ is a go-to process for mixing engineers and musicians alike. It can take some time to really dial in an EQ to get your guitar or bass tone exactly where you want and need it. Here are a few tips to help you get the most out of your EQ pedal(s): Start with the low endSweep parametric EQs to seek and destroy problem frequenciesExperiment with the position in the signal chainDouble the EQ as a boost Start With The Low End 6-string guitars in standard tuning have E2 as their lowest note with a fundamental frequency around 82 Hz. 5-string bass guitars in standard tuning have B0 as their lowest note with a fundamental frequency of about 31 Hz. Unfortunately, frequencies this low are prone to cause issues in a mix if too many low-end signals overlap in the entire mix. On top of that, electric guitars and basses have pickups that are prone to mechanical noise and an entire signal chain that could pick up electromagnetic interference. The result of such noise (along with the low fundamentals) can cause unwanted build-up in the sub-bass and bass frequency bands of the mix. This can really ruin a mix quickly. It's often best to filter out these low frequencies if possible. A good strategy would be to high-pass nearly all instruments except the bass (guitar or synth) and kick drum, though tidying up the low-end of these instruments can yield great benefits for the mix. But wouldn't cutting the fundamentals of the guitar signals ruin the sound? Fortunately for us, much of the tone of a guitar or bass comes from its harmonic profile. In fact, our brains will fill in any missing low-end energy if our ears register the signal's harmonics. This is a win-win when it comes to high-pass filtering. We can remove low-end noise without overly affecting our perception of the lower notes of the instruments! Cleaning up the low-end of our instruments is a great place to start when mixing. It makes sense then, as musicians, to preemptively filter the low-end of our instrument. This helps to reduce noise in the mix while also cleaning up the signal to drive many other pedals with greater signal clarity and accuracy. Related article: Fundamental Frequencies Of Musical Notes In A=432 & A=440 Hz Sweep Parametric EQs To Seek And Destroy Problem Frequencies Another common mix trick that extends to EQ pedals is what I call the "seek and destroy sweep technique". This is where we increase the boost of the frequency-controllable band (preferably with a tighter Q value) and sweep the band across the frequency spectrum. As the boost is swept, we listen for any particularly harsh or problematic frequencies that ring unnaturally or unpleasantly. Once identified, we actually bring the gain of the band down to produce a cut at the problem frequency. Use this technique to find any issues in your guitar or bass signal and reduce the issue by cutting at the undesirable frequency. Listen intently not to overdo the cutting! Experiment With The Position In The Signal Chain As we'll discuss in a moment, EQ can be useful at any stage of an instrument's signal flow. If you've got a larger rig/pedalboard, try experimenting with the placement of the EQ pedal. Try it at the end of the chain or the beginning. Perhaps it sounds best when put after a synth or fuzz pedal. Who knows? Try a few different orders to hear what works best for you. Double The EQ As A Boost EQ pedals can allow us to boost certain frequencies of the signal, sure, but they also often have an overall boost at the output level. Therefore, an EQ pedal can also act effectively as a boost and be used on solos or lead lines that require a bit of extra level (and even a slight alteration in frequency response)! Back to the table of contents. Where Should EQ Pedals Go In The Signal Chain? EQ pedals can go anywhere in the signal chain. That being said, I would typically opt to put an EQ pedal near the front of the chain unless it is needed elsewhere. EQ, in many cases, is a tool used in mixing. When mixing guitar and bass in the studio or live setting, the signal has already gone through a list of units. For example, a signal from a guitar could pass through the following: Effect pedals before the ampThe guitar amplifier’s preampEffects in the amp’s effects loopThe guitar amplifier’s power amplifierThe cabinet’s speakerThe airInto a microphoneThrough a microphone preampInto the mixing console That not to mention all the cable that connects the electronics mentioned above together. If EQ is used in this part of the signal chain, it can certainly be used elsewhere to improve the signal quality and clarity. EQ pedals often work best when put inline after an effect pedal that really alters the character of the signal. These pedals, notable distortion, fuzz and synth pedals, may benefit from extra tone shaping made possible by a dedicated EQ. That being said, EQ pedals can work well at any stage of the signal chain before the guitar amp's power amplifier. Try putting EQ pedals before the amp's input (pre-preamp) and in the amp's effect loop (post-preamp). Related article: How To Order Guitar/Bass Pedals (Ultimate Signal Flow Guide) Back to the table of contents. Related Questions Do guitar effects pedals work with bass guitar? Guitar effects will typically work well with bass guitar signals and vice versa. Some pedals are designed specifically for a certain instrument but will still work with other instruments, though results may vary. The harmonic profiles of guitar and bass signals are similar enough not to cause significant issues in most pedals. Related article: Do Guitar Effects Pedals Work With Bass Guitar? What order should effects pedals go in? Though there are no hard rules in music and art, the typical order of guitar effects pedals for optimal signal flow is as follows: Utility Pedals: tuners, buffers, and switcher pedals.Dynamics pedals: compressors, filters, pitch-shifters, and volume pedals.Gain-based pedals: boost, overdrive, distortion and fuzz pedals.Modulation effects pedals: chorus, flanger, phaser and other modulation pedals.Time-based effects pedals: delay and reverb pedals *Volume pedals can go anywhere in the effects chain.