The Cultivation Foundation Seal
Front of House · Module 5 of 8 · 4 hours

EQ, the room, and feedback

Subtractive first. What a room does to sound, and why the settings that worked last week are wrong tonight.

6 lessons · 2 paper · 3 practice desk · 1 the room

Every lesson is read, then do, then check.

The check carries its answer underneath it. Look only after you have tried — the attempt is what teaches, not the answer.

Lesson 1 of 6Practice desk · Runs in a browser, including a phone

Learning the bands by ear

Read
EQ is useless until the names mean something you can hear. Roughly: below 80 Hz is weight you feel more than hear; 100–250 Hz is body, and where muddiness lives; 400–800 Hz is the boxy, cardboard region that makes a mix sound cheap; 1–4 kHz is where intelligibility lives — consonants, the edge of a snare, whether a lyric can be understood; 6–12 kHz is air and sibilance. You are not learning numbers. You are learning to hear a problem and know roughly where on the dial it lives.
Do
On the practice desk, take one source and sweep a boost slowly across the range, listening. Write down in your own words what each region sounds like to you. Your own words will serve you better than anyone else's vocabulary.
Check

A vocal is clear but sounds thin and small. Which region is missing?

Lesson 2 of 6Practice desk · Runs in a browser, including a phone

Cut before you boost

Read
Boosting adds energy to a system that is already struggling: it eats headroom, it pushes you closer to feedback, and it tends to make a problem louder rather than solving it. Cutting the offending region removes the problem and buys you headroom at the same time. The professional instinct is almost always to find what is wrong and take it away, not to find what is missing and add it. A channel that needs large boosts is usually telling you the microphone is in the wrong place.
Do
Take a muddy source on the practice desk and improve it using cuts only. Then try to achieve the same result using boosts only, and compare how much headroom each approach cost you.
Check

Why is cutting 300 Hz usually better than boosting 3 kHz to get clarity?

Lesson 3 of 6Practice desk · Runs in a browser, including a phone

High-pass everything that is not a kick or a bass

Read
Every open microphone picks up low-frequency energy it has no business contributing: footsteps, air handling, stage rumble, handling noise. Thirty channels of that stacks into a constant mud nothing can be heard through. A high-pass filter throws it away below a set point. Almost nothing on a stage genuinely needs energy below 80 Hz except the kick drum and the bass. This single habit, applied across a whole desk, is the biggest free improvement available to a beginner.
Do
On the practice desk, engage the high-pass on every channel except kick and bass. Listen to the whole mix before and after. Then push one channel's filter too far up and hear what you lose — both edges matter.
Check

You high-pass a vocal at 100 Hz. What did you remove, and what did you gain?

Lesson 4 of 6Paper · Needs nothing but a pen

Feedback, in one sentence

Read
Feedback is a microphone hearing the speaker it is feeding. The sound goes round the loop, gets amplified each lap, and the frequency the room and the system most agree on wins and becomes the howl. That one sentence gives you every available fix, because you can break the loop in only four places: move the microphone, move the speaker, turn the level down, or remove the frequency they agree on. Nothing else is a fix. Everything else is luck.
Do
Write the four fixes down. Then for a stage you can picture, say which of the four you would reach for first and why. Then say which one you would reach for last, and why that one is last.
Check

A vocal microphone starts to ring. Name all four things that could stop it.

Lesson 5 of 6The room · Needs real equipment · the Depot

Ringing out a monitor

Read
Before an audience arrives you deliberately provoke the feedback you would otherwise meet mid-set. You raise the monitor level slowly until it just begins to ring, identify the frequency, cut it narrowly, and continue — two or three times, no more. Each cut buys you a few more decibels of usable level before the system complains. Done past three or four cuts you start removing the music along with the problem, and the monitor sounds hollow and strange.
Do
At the Depot, ring out one wedge under supervision. Say the frequency out loud before you are told it. Then stop at three cuts deliberately and note how much more level you gained.
Check

Why stop at three or four cuts?

Lesson 6 of 6Paper · Needs nothing but a pen

Why last week's settings are wrong tonight

Read
A room is part of the system. Its size, its surfaces and the number of bodies in it all change what reaches an ear. An empty room is bright and reflective; the same room with two hundred people in it is noticeably duller and quieter, because people absorb sound. So a soundcheck in an empty room is a starting point, not an answer, and a recalled setting from a different night was correct for a room that no longer exists. Expect to move things once the audience is in. That is not a failure; that is the job.
Do
Write down three things that will be different between your soundcheck and the third song of the set. For each one, predict which direction you will have to move and roughly how much.
Check

The mix was perfect at soundcheck and sounds dull once the room fills. What happened?

For whoever is teaching it

Instructor notes

  1. The ear-training sweep is the whole foundation of this module. Do not shorten it, and do not give students your vocabulary — make them write their own.
  2. Four of six lessons run on paper or the practice desk. Only ringing out a wedge needs the Depot.
  3. Teach the one-sentence definition of feedback before any technique. Students who have only been taught techniques panic; students who know the loop reason it out.
  4. The four-fixes list is worth memorising. Ask for all four every time, not just the one they would use.
  5. Ringing out needs supervision, hearing protection available, and a hard cap on how loud it gets. Set the cap before you start.
  6. The high-pass lesson produces the biggest audible improvement of the whole course. Let them hear the whole mix before and after — it is the moment the course earns their belief.
  7. Expect resistance to 'cut, do not boost' from anyone who has used a home stereo. Demonstrate the headroom cost rather than arguing.

Slide running order

What goes on the screen.

  1. The frequency range as one bar, regions labeled in plain words
  2. The same source, cut to fix versus boosted to fix — headroom shown for each
  3. Thirty channels of low rumble stacking into mud
  4. The feedback loop as a circle: mic, desk, speaker, back to mic
  5. The four places the loop can be broken
  6. A wedge being rung out: three narrow cuts, level gained at each
  7. The same room empty and full, with the high end visibly absorbed

If you want more

Extra credit

  1. Sweep a boost across any music you have on any EQ you can find, and name the regions in your own words. Fifteen minutes of this is worth more than reading about frequencies for an hour.
  2. Listen to a room you are already in — a hall, a church, a bar — and describe what it is doing to sound before anyone plugs anything in.
  3. Find a recording of feedback and work out, from the pitch alone, roughly which region the loop settled on.
Module 6 · Monitors — the band's world, not yours →All eight modules