Chapter 14 — Quiz

Twenty-five questions to check your grip on microphones, polar patterns, placement, gain, and why sound is half the picture. Answer from memory, then check the key at the end — each answer has a one-line explanation, and there's a "review by question" map so you know where to reread. Multiple choice, true/false (justify your answer), short answer, and a few "what's wrong with this recording?" listening scenarios.

Multiple choice

1. The single most important reason a cheap microphone six inches from a mouth beats an expensive one across the room is:

  • A) cheap mics are secretly better
  • B) closeness improves the ratio of direct (clean) sound to reflected room sound and noise
  • C) expensive mics need phantom power
  • D) the camera's mic is disabled when an external one is used

2. A lavalier microphone is best described as:

  • A) a long directional mic on a pole
  • B) a rugged stick you hold at your mouth
  • C) a tiny clip-on mic worn on the person, near the chest
  • D) the microphone built into the camera

3. Most lavalier mics use which polar pattern, and why?

  • A) shotgun, to reach across a room
  • B) cardioid, to reject the rear
  • C) omnidirectional, because being close already beats the room and omni forgives head-turns
  • D) bidirectional, to catch two people

4. A shotgun mic achieves its narrow, directional pickup mainly through:

  • A) a very large diaphragm
  • B) an interference tube that cancels off-axis sound
  • C) built-in noise reduction software
  • D) phantom power alone

5. You are recording dialogue in a small, hard-surfaced, echoey room and your shotgun sounds hollow and "roomy." The better tool is usually:

  • A) the camera's built-in mic
  • B) a supercardioid / hypercardioid
  • C) a longer shotgun
  • D) an omnidirectional mic across the room

6. On a dBFS meter, 0 dBFS represents:

  • A) perfect silence
  • B) the ideal level for dialogue
  • C) the absolute maximum — the clipping ceiling you must never hit
  • D) the noise floor

7. You should set your gain so that dialogue peaks around:

  • A) 0 dBFS
  • B) -12 dBFS
  • C) -40 dBFS
  • D) +6 dBFS

8. "On-camera sound" is compromised by default because:

  • A) camera mics are always broken
  • B) the mic sits exactly as far from the subject as the camera, which is placed for the frame, not the sound
  • C) it can't be recorded in stereo
  • D) it always clips

9. The three placement rules for a dialogue mic are:

  • A) loud, bright, centered
  • B) close, on-axis, out of frame
  • C) wireless, powered, balanced
  • D) high, wide, distant

10. Double-system sound means:

  • A) using two cameras
  • B) recording the same mic twice
  • C) the mic records to a separate device from the camera, synced later in the edit
  • D) recording in surround sound

11. A boom is:

  • A) a type of microphone capsule
  • B) a long pole that holds a mic close and just out of frame (and the technique of using it)
  • C) a low-frequency sound effect
  • D) the built-in camera mic

12. Which mic is the honest, expected choice for a reporter doing person-on-the-street interviews at a noisy festival?

  • A) a hidden lav
  • B) an on-camera mic
  • C) a handheld "stick" mic held at the mouth
  • D) a boomed shotgun from ten feet

True / False — and justify it

For each, mark True or False and write one sentence of justification. A right T/F with wrong reasoning earns nothing.

13. "A shotgun mic zooms in on sound, so it can pull a clear voice from across a stadium."

14. "If a recording is a little too quiet but clean, you can raise it in the edit; if it's clipped, you usually can't fix it."

15. "Because the meter showed a healthy -12 dBFS, the take is definitely good."

16. "An omnidirectional lav can't reject the room, which makes it a poor choice for a close-up interview."

17. "Automatic gain control (AGC) is the safe choice because the camera sets the level for you."

18. "You should hide a lav wherever it's easiest; placement doesn't affect the sound much."

19. "Recording clean dialogue is partly an accessibility issue, because it produces accurate captions."

Short answer

20. In one sentence, define room tone and give one reason an editor needs it.

21. Explain the difference between "on-axis" and "off-axis," and how a directional mic's off-axis rejection helps you.

22. Why do many professionals record a lav and a boom at the same time on an important interview? Name the practice.

What's wrong with this recording?

Diagnose the audio problem and prescribe the specific fix.

23. A beautifully lit interview: the picture is crisp, but the voice sounds like it's coming from the far end of a bathroom — hollow, with a wash of echo around every word. The subject is seated 12 feet from the camera, whose built-in mic recorded the sound. What's wrong, and what are the two fixes?

24. A talking-head sounds close and clear until the subject gets excited and emphasizes a word — at which point that word cracks into an ugly buzz, then the clear sound returns. What happened, could it be fixed in post, and how do you prevent it next time?

25. A hidden lav delivers a warm, present voice, but every time the subject moves their arm there's a soft scritch-scritch, and when they turn to look at a second person the voice goes dull and drops in level. Name the two distinct problems and the fix for each.

Answer Key

Reveal answers and explanations **1. B** — The whole thesis of the chapter: closeness wins the *direct-to-reverberant ratio*, so the voice dominates the room and noise. Placement beats price. **2. C** — A lav is a tiny clip-on worn on the person near the chest; being on the talent keeps it always close. **3. C** — Omnidirectional. A lav is already close, so it doesn't need rejection, and omni is natural and forgives the head turning off-axis. **4. B** — The interference tube causes off-axis (side-arriving) sound to partly cancel, giving the narrow lobar pattern. **5. B** — A supercardioid/hypercardioid rejects room reflections without a shotgun tube's indoor roominess. Great interior dialogue mic. **6. C** — 0 dBFS is the digital ceiling and the clipping point; every usable level is a negative number below it. **7. B** — Aim dialogue peaks around -12 dBFS: loud and clean with headroom below 0. **8. B** — The on-camera mic is stuck at the camera's distance, and the camera is placed for the frame (usually too far for good sound). **9. B** — Close, on-axis, out of frame. Miss one and good gear sounds mediocre. **10. C** — Double-system: mic to a separate recorder, synced in the edit (Chapter 15's opening topic). **11. B** — The boom is the pole that gets the mic close and just out of frame — and, by extension, the technique. **12. C** — A handheld stick; in reporting genres the mic is *expected* to be visible, and it sits right at the mouth (great proximity, rugged). **13. False** — A shotgun is *directional*, not telephoto for sound; it narrows what it hears but still obeys close-is-king. Across a stadium it just captures a narrow slice of distant, roomy sound. **14. True** — A quiet-but-clean take can be lifted (at the cost of some added hiss); a clipped peak has had its waveform chopped flat and destroyed, which no software rebuilds. **15. False** — The meter shows *level*, not *quality*; a perfect -12 can still be full of rustle, hum, wind, or echo. Only headphones reveal quality. **16. False** — Precisely because a lav is worn close, it doesn't need rejection; omni is the natural, forgiving choice and sounds excellent up close. **17. False** — AGC re-rides the level constantly: in pauses it cranks the gain and the noise floor swells (pumping/breathing). Set gain manually. **18. False** — Placement is everything for a lav: off-center or against fabric causes dull sound, drop-outs, and rustle. Center it high on the sternum, away from rubbing cloth. **19. True** — Clean, close audio yields accurate captions (including automatic transcription); muddy audio garbles them, failing the viewers who rely on captions. **20.** Room tone is the ambient sound of a location when no one is talking and nothing is happening (fridge hum, HVAC hiss, the character of the air). An editor lays it under cuts and gaps so silence doesn't sound "dead" and so mismatched takes blend — it's the connective tissue of a dialogue edit. **21.** "On-axis" is the direction a mic points and hears best; "off-axis" is every other direction, which a directional mic hears less or rejects. You point the on-axis (sensitive) direction at the mouth and let the off-axis rejection land on the noise — keeping the subject, losing the room. **22.** Two-mic safety: the lav is the consistent, always-close *backup* that survives movement, and the boom is the more open, natural *preferred* sound. Running both means one covers the other if a cable rustles, a battery dies, or an aim drifts — and it gives the editor a choice. **23.** The mic was far too far away (12 feet, on the camera), so the room's reflections overwhelm the direct voice — a distance/placement failure, not a gear failure. Fixes: (1) get a mic *close* to the mouth — a lav on the subject, or a boom just out of frame; (2) decouple mic from camera (off-camera sound) so the camera can stay at 12 feet while the mic is near the mouth. Killing some room reflections (soft furnishings) helps but the core fix is *closeness*. **24.** The gain was set too high, so the loud emphasized word exceeded 0 dBFS and *clipped* (the crack/buzz). It generally *cannot* be fixed in post — the peak's waveform is gone. Prevent it by setting gain against the subject's *loudest* real delivery, leaving headroom (peaks near -12, never hitting 0), and, if possible, recording a safety track a few dB lower. **25.** Two separate problems: (a) **clothing/cable rustle** — the mic head is rubbing fabric and/or the cable is transmitting movement; fix by mounting the mic where cloth won't touch it and taping a small strain-relief loop below the head. (b) **off-axis drop-out** — the mic is off-center (or the subject turns their mouth away from it), dulling the voice and dropping level; fix by centering it high on the sternum so head-turns don't change the level. Both are on-set placement fixes, not post fixes.

Review by question

  • Sound is half the picture / proximity (§14.1): 1, 23
  • Mic types — lav, shotgun, boom, handheld (§14.2): 2, 11, 12, 13
  • Polar patterns & off-axis rejection (§14.3): 3, 4, 5, 16, 21
  • Placement — close, on-axis, out of frame (§14.4): 9, 18, 22, 25
  • Gain, levels, clean signal (§14.5): 6, 7, 14, 15, 17, 24
  • On-camera vs off-camera / double-system (§14.6): 8, 10, 26-scenario
  • Room tone & the edit (§14.1, §14.4): 20
  • Accessibility (§14.6): 19

Missed more than a few? Reread the flagged sections, then redo Exercises 7, 8, and 12 with headphones — hearing the difference fixes what rereading can't.