Appendix A: The Frequency Chart

This is the page the rest of the book keeps pointing at. Chapter 4 taught you the band vocabulary, Chapter 22 taught you how to act on it, and Chapter 30 taught you how to diagnose with it. This appendix puts all of it on one wall-friendly reference: the six bands, where every common instrument actually lives, the five problem zones that cause most bad mixes, and the classic EQ moves — with the disciplines that keep them honest.

One warning before the numbers, because the numbers are about to look very authoritative: every figure on this page is an anchor, not gospel. Your kick, your voice, your room will sit a little left or right of every range printed here. The chart gets you to the neighborhood. Your ears find the house.

 20 Hz        60          200          500           2 k           6 k        20 kHz
  │    SUB    │    LOWS    │  LOW-MIDS  │    MIDS     │  HIGH-MIDS  │    AIR    │
  ├───────────┼────────────┼────────────┼─────────────┼─────────────┼───────────┤
  │ felt more │ warmth,    │ body — and │ tone, knock,│ presence,   │ sheen,    │
  │ than heard│ punch,     │ the mud    │ honk, vocal │ attack —    │ breath,   │
  │ 808s, kick│ bass body  │ zone       │ intelligib. │ and harsh   │ cymbals   │
  ├───────────┼────────────┼────────────┼─────────────┼─────────────┼───────────┤
  │ too much: │ too much:  │ too much:  │ too much:   │ too much:   │ too much: │
  │ rumble,   │ boomy,     │ muddy,     │ honky,      │ harsh,      │ brittle,  │
  │ flab      │ thick      │ blanketed  │ boxy, nasal │ fatiguing   │ hissy     │
  │ too little│ too little:│ too little:│ too little: │ too little: │ too little│
  │ no weight │ thin, cold │ hollow,    │ distant,    │ dull, far   │ dead,     │
  │           │            │ scooped    │ vague       │ away        │ lo-fi     │
  └───────────┴────────────┴────────────┴─────────────┴─────────────┴───────────┘

The six bands from Chapter 4, with the symptom words each band produces when it's over- or under-served.

The Six Bands

Sub (below 60 Hz). This is the band you feel in your chest before you hear it in your ears — 808 fundamentals, the bottom octave of a kick, the lowest reaches of synth bass. Most consumer playback can't reproduce it at all, which is why Chapter 26 exists: phone speakers infer the sub from its harmonics. Too much sub and the mix gets flabby and eats all your headroom; meters climb while loudness doesn't. Too little and the track has no physical weight — it sounds fine on earbuds and small in the car. Almost nothing except bass instruments belongs down here, which is why Chapter 22's high-pass discipline starts paying rent in this band.

Lows (60–200 Hz). Warmth and punch. The body of the kick, the meat of the bass guitar, the chest of a low voice, the boom of an acoustic guitar's soundhole. This band makes a record feel full. Too much: boomy, thick, the bass note that hangs over everything — and in untreated rooms, this is also where room modes lie to you hardest (Chapter 10). Too little: thin, cold, a mix that feels like it's standing on stilts.

Low-mids (200–500 Hz). Body — and the mud zone. Nearly every instrument has energy here: vocals, guitars, piano, snare, pads, toms. That's exactly the problem. Each track sounds warm and full alone; stacked, they pile into the blanket that Chapter 22 calls a committee decision. This is the most-cut region in mixing, and the founding wound of the whole book lives here — the low-mid smear that buried Jaylen's vocal sample in the car. Too much: muddy, congested. Too little: hollow, scooped, that "smiley-face EQ" emptiness where a mix has boom and sizzle but no torso.

Mids (500 Hz–2 kHz). The center of the musical universe and the band your ear evolved to care about most. Vocal vowels, guitar knuckle, snare tone, the intelligibility of almost everything. Telephone speakers reproduce roughly this band alone, and you can still follow the song — that's how much information lives here. Too much: honky, boxy, nasal, cheap. Too little: distant and vague, a mix you can hear but can't quite grab.

High-mids (2–6 kHz). Presence, attack, edge — and the harshness tightrope from Chapter 22. Consonants live here, along with pick attack, snare crack, and the kick's beater click. Your ear is most sensitive in this region (the equal-loudness story from Chapter 4), so small moves are loud decisions. Too much: harsh, fatiguing, a mix that makes you reach for the volume knob after two minutes. Too little: dull, polite, far away.

Air (6 kHz and up). Sheen, breath, cymbal shimmer, the expensive-sounding top on a well-recorded vocal. Sibilance sits at the bottom of this band, which is why air boosts and de-essers travel together (Chapter 29). Too much: brittle, hissy, sandpaper. Too little: dead and dated, like a cassette found in a glovebox. Chapter 22's rule applies doubly here: air is fatigue's first victim, so verify every air boost at matched loudness after a rest.

Instrument Frequency Ranges

Fundamentals are where the note's pitch lives; harmonics and body are where its character fills in; the presence zone is where you reach when it needs to cut through. Ranges are typical, not universal — tunings, voices, and samples vary.

Two patterns worth noticing. First, almost every row touches 200–500 Hz — that's why the mud zone is a committee problem, never a single culprit. Second, presence zones cluster at 2–5 kHz, which is why Chapter 22 calls that region a tightrope: everybody wants to stand on it at once.

Problem Frequencies Quick Reference

These five zones cause most of the complaints that send people to Chapter 30's emergency room. Each entry: what you hear, the 60-second check, the fix. Note that boxiness and honk blur into each other — Chapter 30's symptom table files the boxy honk at 300–600 Hz; the nasal honk is its upper neighbor.

For thin, boomy, lifeless, and small — the symptoms that aren't a single frequency zone — use Chapter 30's full symptom table. That chapter is this page's big sibling.

EQ Move Cheat Sheet

The classic carves, framed exactly as Chapter 22 framed them: starting points to audition, never presets to trust. Every move ends with a matched-loudness A/B or it didn't happen.

How to Use This Chart

Sweep and destroy, then put the searchlight down. When a track sounds wrong somewhere you can't name, use Chapter 22's technique: boost a narrow bell a few dB, drag it across the suspect region, find the frequency that makes the problem bloom, then flip the boost into a cut. But remember the overuse warning that came with it — sweeping makes every frequency sound guilty when it's boosted. One or two convictions per track. If you've got six cuts on one channel, you're EQing the sweep, not the song.

The matched-loudness law. Louder sounds better — every time, to every ear, including yours. Any EQ move that adds level will flatter you into keeping it. Match the processed and bypassed loudness before you judge, every move, no exceptions. This is the law Chapter 22 built and Chapters 26 and 32 re-ratified. Matched-loudness or it didn't happen.

The no-solo rule. Solo is for finding a problem frequency; the decision gets made in the full mix. A vocal EQ'd to perfection in solo is EQ'd for a context that will never exist. The mix is the only courtroom, because the mix is the only thing anyone will ever hear.

Borders are fuzzy. The six bands aren't walls; they're neighborhoods that blend into each other. A "boxy" vocal at 280 Hz and a "muddy" one at 320 Hz are the same problem wearing different name tags. Use the vocabulary to aim your attention, then trust the sweep and your ears over the printed border.

And when the chart fails you — when no cut anywhere makes the mix open up — stop EQing. That's the Chapter 20 threshold knocking: a mix problem is usually an arrangement problem wearing a disguise. Too many parts in one band is a mute-button problem, and no chart fixes it. Chapter 16 does.

Tape this page up. Then earn the day you stop needing it.