Equalization

I was at the NAMM convention in Anaheim one year, and Eddie Kramer—the legendary engineer behind Jimi Hendrix and Led Zeppelin—was presenting at the Waves Audio booth. During the Q&A, I asked him about his approach to EQ: did he prefer additive or subtractive equalization? He looked at me, laughed, and said, “Boostier!”—as if the question itself was ridiculous. The crowd loved it. I walked away thinking about it for days. The textbook answer is to cut first—subtractive EQ uses less headroom and generally sounds more natural (the phase shift, contrary to the common belief, is the same magnitude for an equal boost or cut). But here was one of the greatest engineers in history dismissing the whole debate with a made-up word. The truth, as it usually does in this business, lies somewhere in the middle. A great engineer does both. You cut to remove problems and boost to enhance character. The skill is knowing which to reach for and when.

At its simplest, an equalizer boosts or cuts certain frequencies in an audio signal. Think of the treble and bass knobs in your car—that is EQ. The controls we have in the studio are far more precise, but the concept is the same: shape the tonal balance of a sound by adjusting how loud specific frequency ranges are relative to each other.

EQ is fundamentally a tonal tool, not a volume tool. Yes, boosting or cutting frequencies will change the overall level to some degree—boost enough of anything and the signal gets louder; cut enough and it gets quieter. But that is a side effect, not the purpose. The purpose of EQ is to change the tonal character of the sound. A vocal that sounds muddy does not need to be turned down; it needs the low-mids cut. A guitar that sounds dull does not need to be turned up; it needs the high-mids boosted. EQ is the tool you reach for when the volume is right but the sound is wrong.

Before you touch a single EQ band, you need to understand what lives where. The entire audible spectrum (20 Hz to 20 kHz) can be broken into five main regions, each with its own character and vocabulary. Learn these words—they are how clients, producers, and other engineers communicate about sound:

Low (20–200 Hz) — If a client wants to “feel” the bass or wants more “punch,” these are the frequencies to adjust.

Low-Mid (200–750 Hz) — Can add “fullness,” “depth,” and “thickness.” However, too much around 500 Hz results in a “muddy” sound.

Mid (750–1500 Hz) — Easily audible to the human ear. In isolation, they resemble the sound of a telephone. Too much sounds “honky”; too little sounds empty.

High-Mid (1.5–5 kHz) — Adds “clarity,” “brightness,” and “presence” or gives a track more “bite.” Too much sounds “thin” and “harsh” or causes “ear fatigue.” This is the most sensitive range of human hearing.

High (5–20 kHz) — Adds “sparkle,” “brilliance,” and “air.” Too much sounds “brittle”; not enough sounds “distant.”

These are the words you will hear from clients. They usually will not say they need a cut at 500 Hz and a boost at 5 kHz. They will say their voice sounds “muddy” or they want it to be more “clear.” It is your job as the engineer to translate what they're saying into the appropriate action. The frequencies that constitute “muddy” for one instrument don't necessarily correspond to another. Understanding the frequency range of each instrument is essential. Part of that translation is knowing each instrument's fundamental (the root pitch) versus its harmonics (the overtones that give it character and brightness): “muddy” on a male vocal lives in a different place than “muddy” on a kick, because their fundamentals and harmonic stacks sit in different ranges.

Understanding which instruments live in which frequency ranges—and where they overlap—is the key to effective EQ. The detailed EQ Reference Charts later in this chapter provide specific frequency recommendations, Q values, and boost/cut suggestions for every common instrument. Use those charts as your hands-on reference when you are actually at the console. For now, internalize the vocabulary above so that when a client says “the kick needs more punch” you immediately think 100–180 Hz, or when they say “the vocal is muddy” you reach for a cut around 250–500 Hz.

Every equalizer—whether a stock plugin, a third-party powerhouse, or a vintage hardware unit—shares the same core controls. In Pro Tools, open Avid → EQ III 7-Band on any track to see them in action (the 7-Band variant is the one shown in the figure below).

Frequency — The center frequency you are targeting. On the EQ graph, the left edge is 20 Hz (the lowest audible frequency) and the right edge is 20 kHz (the highest). Choosing the right frequency is the most important EQ decision you make—boost the wrong one and you amplify a problem; cut the right one and the mix opens up instantly.

Gain — How much you boost or cut the selected frequency, measured in dB. Most EQs offer up to ±18 dB. For corrective moves—fixing a problem—I rarely go beyond ±4 dB; if a fix needs more than that, the trouble is usually upstream, in the mic placement, the arrangement, or the source itself. Creative tone-shaping is a different story: broad musical shelves, a Pultec-style low-end boost, or an air-band lift routinely run well past 4 dB by design (the parallel-EQ trick later in this chapter leans on a much larger boost on purpose).

Quality Factor (Q) — Controls the width of the EQ curve. This is where the art lives. A narrow Q (high Q value, such as 8.0–10.0) affects only the chosen frequency and its immediate neighbors—surgical precision for removing a ring, a resonance, or a specific problem. A wide Q (low Q value, such as 0.5–2.0) affects a broad range of frequencies around the center—musical, gentle shaping that changes the overall character of a sound. As a rule of thumb: cut narrow, boost wide. Narrow cuts remove problems without affecting surrounding frequencies. Wide boosts enhance character without sounding unnatural.

Filter Type — The shape of the EQ curve. There are three main types—peak, shelf, and pass—each serving a different purpose. We will cover each in detail below.

Peak Filter (Bell)

The most commonly used filter. A bell-shaped curve that boosts or cuts symmetrically around the chosen frequency. Its width comes from the Q control covered earlier in this chapter.

With a wide Q, a peak filter makes broad tonal adjustments—adding warmth by gently boosting the low-mids, or adding “air” with a wide boost above 10 kHz. These moves shape the overall character of a sound. With a narrow Q, the same filter becomes a surgical scalpel—removing a resonant ring from a snare drum at 900 Hz, or taming a harsh overtone on an electric guitar at 3 kHz. Knowing when to reach for wide versus narrow is one of the most important EQ skills you will develop.

A notch filter is a peak filter with maximum Q and full cut—it removes a single frequency almost entirely without touching anything around it. Use it to eliminate electrical hum (60 Hz and its harmonics), feedback in a live setting, or a specific resonance ruining an otherwise good recording.

The EQ III 7-Band plugin shown earlier illustrates how most parametric EQs work: each of the five colored bands (LF, LMF, MF, HMF, HF) has independent frequency, gain, and Q controls—LMF, MF, and HMF are peak filters, while LF and HF switch between peak and shelf (and default to low shelf and high shelf). The frequency graph displays the combined curve of all bands plus the high-pass and low-pass filters. When you adjust one band, watch how it affects the overall curve. Learning to read this graph is just as important as learning to hear the changes.

Shelf Filter

A shelf filter boosts or cuts everything above (high shelf) or below (low shelf) the selected frequency. Unlike a peak filter, the curve does not return to zero—it continues at the boosted or cut level for the remainder of the spectrum, resembling a shelf.

A high shelf boost above 8–12 kHz adds air and sparkle to a vocal or drum overhead. A high shelf cut tames harshness or excessive brightness. A low shelf boost below 100–200 Hz adds warmth and weight to a bass or kick drum. A low shelf cut thins out a boomy recording or reduces low-end buildup.

When I want to add overall brightness to a vocal without targeting a specific frequency, a high shelf is my first reach—it is broader and more natural-sounding than a narrow peak boost. The Pultec EQP-1A, one of the most legendary EQs ever made, is essentially a shelf EQ with a unique twist: it can boost and cut at the same frequency simultaneously, creating a distinctive curve that no other EQ can replicate. Engineers have been using this “Pultec trick” on vocals, bass, and mix buses since the 1950s. In practice the move is simple: boost the Low band around 60–100 Hz for weight, then add a little Low Cut at roughly the same frequency—the cut tightens the very bottom the boost just added, leaving a low end that reads as big and defined rather than muddy.

Pass Filter (High-Pass / Low-Pass)

Pass filters are your cleanup tools—they remove everything above or below a cutoff frequency. Think intuitively: a high-pass filter lets highs pass through and cuts the lows. A low-pass filter lets lows pass through and cuts the highs.

The high-pass filter is the single most-used EQ tool in mixing. Nearly every track that is not kick drum or bass benefits from rolling off everything below its useful range. A vocal does not need 40 Hz. An acoustic guitar does not need 80 Hz. A snare does not need 60 Hz. These sub-frequencies are not audible as musical content—they are rumble, handling noise, and proximity effect that accumulate across dozens of tracks and turn your low end into mud. High-pass everything that does not need to be there, and your mix will open up immediately.

A low-pass filter clears the high end—cutting hiss, removing non-essential high frequencies from instruments like kick, bass, or low pads. I use low-pass filters on kick drums to remove the high-frequency “tick” when I want a rounder, deeper sound, and on background vocals to push them slightly behind the lead by darkening their tone.

Pass filters also have a slope, measured in dB per octave. A gentle 6 dB/octave slope rolls off gradually—useful when you want a subtle tonal change. A steep 24 dB/octave slope cuts aggressively—useful when you need to eliminate a specific frequency range without affecting what is nearby. Most parametric EQs let you choose the slope, and the right choice depends on how surgical you need to be. Steeper slopes are not free: the steeper the filter, the more phase shift it introduces around the cutoff, and very steep filters (24–48 dB/oct) can add a slight resonant bump or ringing right at the corner frequency that sounds unnatural on transient material. Use gentle slopes (6–12 dB/oct) for musical, transparent rolloffs; reach for steep slopes only when you need to surgically remove a range and can live with the side effects.

When a high-pass and low-pass are used together, the result is a bandpass filter—only the midrange passes through, creating the classic “telephone effect.” This is a popular creative effect on vocals, synths, and drums for lo-fi or vintage character.

A parametric EQ lets you select frequency, Q, and gain for each band—full control over what you are adjusting and how precisely. This is what you will use in the studio 99% of the time. The EQ III and FabFilter Pro-Q are parametric EQs.

A graphic EQ has fixed frequencies and fixed Q—the only control is gain, via a row of faders. Graphic EQs come in octave-band (10 faders), 1/3-octave (31 faders), or fewer. They are less precise than parametric EQs but faster for broad adjustments. In the studio, graphic EQs are primarily used for room correction and monitor tuning. In live sound, they are essential for eliminating feedback frequencies quickly.

“I always like to listen to the sound source first, whether it's recorded or live, and see how well it holds up without any EQ or whatever… To me it's kinda like salting and peppering your food before you've tasted it.”

—Bruce Swedien, interviewed in Bobby Owsinski's The Mixing Engineer's Handbook

Every EQ situation is different, and there is no formula that works for every instrument. The skill is hearing what you want and knowing which tool gets you there. That comes with practice—there is no shortcut. Pull up a Signal Generator plugin on a mono track, set it to sine wave, and spend time learning what different frequencies sound like. Have a friend set random frequencies and see if you can identify them. This exercise builds the ear-to-frequency association that separates beginners from professionals.

The Sweep Technique

This is the most essential EQ skill you will learn. Used on almost every track I mix, it is the fastest way to find and fix problems you can hear but cannot pinpoint.

1. Insert a parametric EQ on the track. Activate one band only.
2. Set the band to a peak filter, narrow Q (8–10), boost to full (+12 to +18 dB).
3. Slowly sweep the frequency across the spectrum while the audio plays. Every problem frequency will jump out at you—mud, ring, harshness, hum, sibilance.
4. Stop sweeping when the offending frequency makes itself known.
5. Set the gain back to zero, then cut until the problem disappears (usually 2–4 dB is enough).
6. Widen the Q until the cut sounds natural—narrow enough to be surgical, wide enough to not feel like a hole.

Subtractive vs. Additive EQ

The opening anecdote established the principle: cut to remove problems, boost to enhance character. Both are valid tools.

In practice: if a vocal sounds muddy, cut the low-mids. If a guitar sounds dull, boost the presence range. Try to keep corrective moves within ±4 dB. If a fix needs more than that, the problem is probably not EQ—it is the source, the mic placement, or the arrangement. (Creative tone-shaping, as noted above, is free to go further.)

Parallel EQ

Do not underestimate parallel EQ. Instead of EQing a track in place, you set up a brightened or shaped duplicate on an Aux and blend it underneath the original. The result is more natural than aggressive in-place EQ because the unprocessed original stays in the mix.

1. Create a stereo Aux track. Insert a parametric EQ.
2. High-pass everything below 1 kHz on the Aux's EQ.
3. Boost a high shelf around 10–12 kHz by about 20 dB (this is the sparkle-maker—safe only because it runs in parallel and you blend in just a touch; 20 dB as a direct insert would be destructive).
4. Send a small amount of any dull track (vocal, drum bus, acoustic guitar) to this Aux.
5. Blend to taste. The brightness layers underneath the original instead of replacing it—the same trick that makes the Pultec EQP-1A's simultaneous boost/cut so musical.

This works especially well with analog EQ: track to the Aux through a hardware unit, record the result, mix it underneath the dry track. You get the analog character without committing it to the source.

Musical Key Awareness

Every note in the musical scale corresponds to a specific frequency. If a bass note in the key of A is booming, you know exactly where to look—and you know that cutting at the right octave of A will affect every A note in the song without touching the rest. Understanding your song's key turns EQ from guesswork into precision.

The fundamentals and harmonics for a few common keys (each row is the same note in different octaves):

Practical example: a song in A minor has a bass note booming at 110 Hz. Cutting at 110 Hz with a narrow Q tames the note that is causing the issue and leaves every other note in the bass line alone—because 110 Hz is the fundamental of A2 (the A two octaves below concert pitch), so a narrow cut there lands on that one note and nothing else. The same cut at 100 Hz (a non-musical frequency) would dull every note within the cut's bandwidth, not just the problem A.

EQs like FabFilter Pro-Q and Waves H-EQ display the piano keyboard alongside the frequency spectrum, making this technique intuitive—you see the note name as you set the frequency. Even on EQs without a visible keyboard, the table above gives you the targets.

EQ in the Signal Chain

Where you place EQ matters. EQ before compression changes what the compressor reacts to—cutting low-end rumble before the compressor prevents it from wasting gain reduction on frequencies you do not want. EQ after compression can compensate for the tonal changes compression introduces, especially the high-frequency loss that heavy compression often causes. We will explore this relationship in depth in the next chapter on dynamics processing.

Track-level vs stem-level EQ. Track-level EQ targets one element—the kick, the lead vocal, the rhythm guitar—and surgically fixes problems specific to that source. Stem-level EQ (on a bus or Aux that contains multiple tracks—e.g., a Drums Aux or a Vocals Aux) affects everything inside that bus equally. Stem-level is for global tonal shaping: a 1 dB high-shelf boost on the Drums bus opens up the entire kit at once; a low-shelf cut on the Vocals bus tightens every vocal layer in unison. Most pro mixes use both—track-level for problems, stem-level for character. The six-bus Aux structure you set up in Chapter 14 is the foundation for stem-level EQ work. When you EQ a bus, you are effectively making that same EQ move on every instrument inside it at once—so a 1 dB shelf on the Drum bus is a far broader, more powerful stroke than a 1 dB shelf on a single track. Stem EQ does a lot with a little; reach for small moves.

EQ during recording—last resort. Try adjusting mic placement before reaching for an EQ. Moving a microphone two inches can solve a problem that no amount of equalization can fix. In mastering, if you need more than a few dB of EQ, something is wrong with the mix.

When EQ is the wrong tool: harmonic distortion. Sometimes what feels like an EQ problem is actually a tone problem that EQ can only fake. A dull recording has no high-frequency content—boosting 10 kHz with EQ amplifies the noise floor and the hiss without adding the harmonic content a bright mic would have captured. Saturation, harmonic exciters, and tape emulation (covered in Chapters 9 and 16) generate new harmonic content from the existing signal, which EQ cannot do. On a flat-sounding bass DI, a saturator at 200–400 Hz adds harmonics that make the bass audible on small speakers without changing the fundamental. On a dull vocal, a tape emulation adds high-frequency information that EQ cannot manufacture. Reach for EQ to shape what is there. Reach for saturation when there is nothing to shape. One nuance, though: many analog EQs add harmonic character of their own as you push them—an API sounds “punchy,” a Pultec “smooth and thick”—and that coloration is a big part of why engineers reach for a specific unit. An analog (or analog-modeled) EQ does add harmonic content; a clean digital EQ does not. Choose the EQ for its color as much as its curve.

Dynamic EQ

A dynamic EQ combines equalization with compression: each EQ band activates only when the signal in that frequency range exceeds a threshold. Think of it as a compressor that targets a specific frequency instead of the entire signal. If a vocal is harsh only on the loudest notes, a dynamic EQ can cut 3 kHz only when those notes hit—leaving the quieter, non-harsh passages untouched. A static EQ cut would dull the entire performance. Dynamic EQ is surgically precise in a way that static EQ cannot be, and it has become one of the most important tools in modern mixing. FabFilter Pro-Q and TDR Nova (free) both offer dynamic EQ per band. How is this different from a multiband compressor? A multiband comp splits the signal into a few wide bands with crossovers and compresses each band's overall level. A dynamic EQ applies a precise, surgical EQ move (any frequency, any Q) only when that band crosses threshold—no crossovers, no phase smear between bands. Multiband = broad level control of a band; dynamic EQ = surgical, frequency-specific, more transparent. For one ringing resonance that only acts up on loud notes, reach for dynamic EQ; for broad tonal balancing of a full mix, multiband.

Mid/Side EQ

Mid/Side (M/S) EQ lets you process the center of the stereo image independently from the sides. The “Mid” channel contains everything identical in left and right (usually kick, bass, vocal, snare). The “Side” channel contains everything that differs between left and right (stereo reverb, panned guitars, wide synths).

This is incredibly powerful in mastering: you can roll off bass in the Side channel to tighten the low end without affecting the kick (Katz, 2014), or boost highs in the Side to add width and air without brightening the center vocal.

But M/S is not just a mastering tool. On individual stereo tracks during mixing it solves real problems:

• Stereo guitar pair—cut everything below 100 Hz on the Side channel to keep low-end mud out of the panned guitars without thinning the center.
• Stereo synth pad—boost a wide air shelf at 12 kHz on the Side to push the pad open and around the listener while leaving the center vocal alone.
• Stereo room mics on drums—cut Side mud (200–400 Hz) and gently boost Side highs to push the room sense outward and behind the close mics.
• Stereo overheads—cut a narrow problem frequency on Side only when the cymbals are harsh on one panned side but the snare bleed in the center is fine.

FabFilter Pro-Q, Ableton's EQ Eight, and most modern mastering EQs support mid/side processing. Once you start hearing the stereo field as two separate signals you can EQ independently, you will use it on more tracks than you would expect.

Linear Phase vs. Minimum Phase EQ

Standard EQs use minimum phase processing, which is computationally efficient and sounds musical—but it introduces phase shifts around the boosted or cut frequencies. In most mixing situations, these phase shifts are inaudible and harmless. But in mastering, where you are processing the entire stereo mix, phase shifts can smear transients and alter the stereo image. A linear phase EQ eliminates these phase shifts entirely, preserving the exact time relationship between frequencies. The trade-off: higher CPU usage and a slight processing delay (latency).

Linear phase has its own artifact, though, and you should know it before you reach for the linear-phase mode automatically. Because the FIR filter linear phase EQ uses has a symmetric impulse response, it can produce pre-ringing—a faint, ghost-like ripple that arrives before a transient instead of after it. On heavily-EQ'd transient material like kick drums and snare, this can soften the attack or create an audible pre-echo, a kind of “smear” in the leading edge of each hit that minimum phase EQs simply do not have. The harder you drive a linear phase EQ (heavier boosts and cuts, especially in the low end), the more pre-ringing you may hear. On a vocal or sustained instrument, this is usually inaudible. On a kick drum where you have boosted 60 Hz by 6 dB, it can take the punch out of the hit.

Use minimum phase EQ for mixing (it sounds more natural on individual tracks and has no pre-ringing). Reach for linear phase when you need phase coherence on the mix bus during mastering, on parallel processing where two correlated copies must stay in time, or on stereo material where minimum-phase shifts would alter the image. On FabFilter Pro-Q the phase mode is a global, plugin-wide setting. Switch a given instance to linear phase only where it actually helps.

Passive vs. Active EQ Design

Passive EQs use only cuts followed by a makeup gain amplifier—no active boosting circuits. The result is a smoother, more musical tonality that many engineers describe as “analog warmth.” The smoothness attributed to vintage valve (tube) equalizers often has less to do with the tubes themselves and more to do with the passive circuit design. The Pultec EQP-1A is the most famous passive EQ—engineers have used it on everything from Frank Sinatra to Beyoncé. Active EQs use powered circuits for both boost and cut, offering more precision and flexibility at the cost of a potentially harsher sound when pushed hard.

Pro Tools ships with the EQ III (1-, 4-, and 7-Band) and the Avid Channel Strip—a Euphonix-derived plugin that combines EQ with dynamics in a single interface. The Channel Strip supports band soloing (Ctrl+Shift+click to hear a band in isolation)—excellent for the sweep technique. Clip Effects EQ allows applying EQ directly at the clip level, non-destructively.

For third-party EQs, FabFilter Pro-Q is the current industry standard—up to 24 bands, dynamic EQ, mid/side, spectrum analyzer, and linear phase mode. Its EQ Match feature analyzes a reference track's spectral shape and applies that curve to yours—use it as a starting point, never a finished EQ; the matched curve will surface its own problems that still need human correction. For analog character, the Universal Audio Pultec EQP-1A and Waves SSL E-Channel are staples.

EQ is the first tool most engineers reach for and the last one most engineers truly master. It looks simple—boost this, cut that—but the difference between an EQ move that opens up a mix and one that makes it worse is entirely in the ear of the engineer. I have watched students boost 5 kHz on a vocal to add presence, not realizing they were also bringing out harshness that would become unbearable over three minutes. I have watched experienced engineers make a single 1.5 dB cut at 300 Hz that transformed a muddy, cluttered mix into something clear and professional. The move was almost invisible on the screen. The difference in the speakers was enormous.

Here is the truth about EQ that no chart or plugin can teach you: every sound is different. A kick drum recorded in a tight booth through a Shure Beta 52 sounds nothing like the same kick in a live room through a Neumann U47 FET. The frequencies are in different places. The problems are different. The character is different. You cannot memorize a formula and apply it to every kick drum you encounter. You have to listen—to the specific sound in front of you, in the specific context of the specific song—and make decisions based on what your ears tell you. The reference charts that follow this section are starting points, not answers. The sweep technique is a method, not a recipe. Your ear is the only tool that matters, and it gets better every single time you use it—with one caveat: ears improve over a career of training, but they get worse over a long session. At hour four, at 4 AM, your ears are fatigued and will lie to you. Take breaks, rest your ears, and make the final calls fresh. The ear improves with training and degrades with overuse; respect both.

One more thing: EQ does not exist in isolation. Every EQ move you make changes how the compressor after it responds, how the reverb sounds, how the instrument sits against everything else in the mix. A boost at 3 kHz on the vocal might sound great in solo but clash with the guitar when you hear them together. Always EQ in context—with the rest of the mix playing, not in solo. Solo is for finding problems; context is for making decisions.

The goal is always the same: make instruments sound more defined, help them coexist without fighting, and preserve the integrity of the original performance. EQ is not about making things “better”—it is about making things right. And by “right” I mean tonal balance: every element holding its own frequency space so nothing masks anything else—EQ is right when each instrument can be heard clearly in its own lane, not when any single track sounds best in solo. Trust your ears, reference your favorite records, and remember that the best EQ move is often the one you decide not to make.

What follows is field-guide reference material—starting points for equalization on common instruments. These are guidelines, not rules. The lesson of this chapter is in your ears; the charts are here for the moments when you want a quick anchor to reach for. Engineers sometimes call these recurring values “magic frequencies”—the same handful of Hz fixes the same problems on record after record.

The chart above illustrates the fundamental frequency range (solid bars) and harmonic/overtone range (faded extensions) for common instruments across the audible spectrum from 20 Hz to 20 kHz. Understanding where each instrument lives in the frequency spectrum is one of the most important skills in mixing and equalization.

Notice how many instruments overlap in the 200 Hz–1 kHz midrange region. This is where “muddiness” accumulates in a mix—when too many instruments compete for the same frequency space. Effective EQ work means carving out space for each instrument by attenuating frequencies where instruments overlap and boosting the frequencies that define each instrument's unique character.

The low end (20–200 Hz) is dominated by kick drum, bass, and the fundamentals of lower-register instruments like tuba and cello. The midrange (200 Hz–5 kHz) is where most musical information lives—vocals, guitars, keyboards, and the body of nearly every instrument. The high end (5 kHz–20 kHz) contains the “air,” sibilance, cymbal shimmer, and the overtones that give instruments their brightness and presence.

Use this chart as your map. When you sit down to EQ an instrument, find it on the chart first—see where its fundamental range lives, where its harmonics extend, and where it overlaps with other instruments in your session. That overlap is where the fights happen, and where your EQ decisions matter most.

The reference tables that follow are your field guide for those decisions. For each common instrument, they provide specific frequencies, Q values, filter types, and whether to boost or cut—along with what each move sounds like in plain language. These are not rules. They are starting points based on decades of collective engineering experience. Print them, bookmark them, and keep them next to your speakers.

BASS GUITAR — EQ Reference

Parametric reference — frequency, Q, boost/cut:

Broad-range reference — what each zone does:

BRASS AND WOODWINDS — EQ Reference

Parametric reference — frequency, Q, boost/cut:

Broad-range reference — what each zone does:

CYMBALS AND HI-HAT — EQ Reference

Parametric reference — frequency, Q, boost/cut:

Broad-range reference — what each zone does:

DRUMS — EQ Reference

Parametric reference — frequency, Q, boost/cut:

GENERAL USE — EQ Reference

Parametric reference — frequency, Q, boost/cut:

GUITAR — EQ Reference

Parametric reference — frequency, Q, boost/cut:

Broad-range reference — what each zone does:

Alternate voicings — a second chart for the same zones; where the two disagree, trust your ears:

HI-HAT — EQ Reference

Broad-range reference — what each zone does:

HORNS — EQ Reference

Broad-range reference — what each zone does:

KICK DRUM — EQ Reference

Parametric reference — frequency, Q, boost/cut:

Broad-range reference — what each zone does:

ORGAN — EQ Reference

Broad-range reference — what each zone does:

PIANO — EQ Reference

Parametric reference — frequency, Q, boost/cut:

Broad-range reference — what each zone does:

SNARE DRUM — EQ Reference

Parametric reference — frequency, Q, boost/cut:

Broad-range reference — what each zone does:

STRINGS — EQ Reference

Broad-range reference — what each zone does:

SYNTHESIZER — EQ Reference

Parametric reference — frequency, Q, boost/cut:

Broad-range reference — what each zone does:

VOCALS — EQ Reference

Parametric reference — frequency, Q, boost/cut:

Broad-range reference — what each zone does:

In the next chapter, we will explore dynamics processing—compressors, limiters, gates, and expanders—the tools that control the volume of your audio with the same precision that EQ controls its tone.