Chapter 12 Quiz — Recording Instruments

Closed book, honest effort. Multiple choice: 1 point each. True/False: 2 points (1 for the verdict, 1 for the justification — a lucky coin-flip with a wrong reason earns half). Short answer: 3 points each. Applied scenario: 5 points. Total: 42. Scoring table at the end. The chapter's closing line promised this quiz would find out whether phase and polarity actually came apart in your head — questions 8 through 11 are where it finds out.

Multiple Choice (15 × 1 point)

1. The chapter's reframe for electric guitar is that you don't mic a guitar — you mic:

  • A) The pickups, as directly as possible
  • B) An amplifier, because the tone you love is the speaker pushing air in a room
  • C) The strings, from above
  • D) The DI signal
Answer **B.** The guitar is only a third of the instrument — pickups, amp circuit, and speaker complete it. The tone worth recording is the speaker's, in air. (D is a legitimate *capture*, but it's the raw electrical signal, not the completed instrument — that's why sims exist.)

2. The brightest, fizziest spot on a guitar amp's speaker is:

  • A) The outer edge of the cone
  • B) The seam where the dust cap meets the cone
  • C) The dust-cap center
  • D) The cabinet's back panel
Answer **C.** High frequencies beam along the speaker's axis and the directly driven center stays most faithful to the fastest wiggles — park a capsule there and you drink fizz from the harshest square inch of the amp. The cap-edge seam (B) is the classic *starting* point precisely because it buys brightness without the full fizz dose.

3. Your mic'd amp tone has a harsh, fizzy glare in the high-mids. Which move addresses it without touching an EQ?

  • A) More preamp gain
  • B) Slide the mic toward the cone's edge
  • C) Flip the polarity on the track
  • D) Use a longer cable
Answer **B.** Position across the speaker's face is a treble control you operate before the take: center is brightest, edge is darkest, and half-inch moves matter. Angling the mic 30–45° off-axis is the other placement fix. (C does nothing useful on a single capture — polarity changes are inaudible on a track playing alone.)

4. Pointing a cardioid at an acoustic guitar's soundhole from eight inches produces boom because the soundhole is:

  • A) Where the guitar's balanced sound exits
  • B) The body's resonator vent, pumping hardest around the body's main low resonance — with proximity effect stacking on top
  • C) Closest to the strings
  • D) Acoustically reflective
Answer **B.** The soundhole is the port where the air inside the box breathes — strongest in the low hundreds of hertz — so on-axis it delivers the box's boom, not the instrument's balance. At eight inches, a cardioid adds proximity bass to the cavity boom: two bass problems, stacked. Aim at the twelfth fret instead.

5. The DI safety doctrine: whenever you mic an amp, record a DI of the same performance. Which of these is NOT one of its payoffs?

  • A) Insurance against a bad mic position discovered at mix time
  • B) Re-amping the performance later
  • C) Layering an amp-sim version under or instead of the mic'd take
  • D) It removes the need for the flip test when blending the DI with the mic
Answer **D.** The doctrine's payoffs are insurance, re-amping, and sim blending. It does *not* exempt you from phase discipline — the moment you blend the DI with the mic'd capture, the mic's air-delay makes the flip test and an alignment check mandatory.

6. Re-amping means:

  • A) Recording the amp twice at different volumes
  • B) Playing a recorded DI signal back out of the DAW into a real amplifier and micing the result later
  • C) Adding a second amp sim in series
  • D) Boosting the amp's signal at the preamp
Answer **B.** A re-amp box (a DI running in reverse — line level back down to instrument level) feeds the stored performance to a real amp, and you mic it as if the guitarist were playing — except the mic can move between "takes" forever. Performance and tone become separate decisions, made on separate days.

7. In a small untreated room, the first-call professional bass capture is:

  • A) A condenser three feet from the cabinet
  • B) The DI
  • C) A room mic for natural ambience
  • D) Two mics on the cabinet for options
Answer **B.** Three stacked reasons: small rooms lie hardest below 200 Hz and pour those lies into any open mic (the DI hears no room); the DI's capture is full-range and consistent — the foundation the mix leans on; and a DI can be re-amped or sim'd into any tone forever. Engineers have cut bass direct since the 1960s — it's the first-call move, not the compromise.

8. Flipping a track's polarity (the ∅ button) does what, physically?

  • A) Delays the signal by half a cycle
  • B) Mirrors the entire waveform across zero — every frequency inverted instantly, by the same amount, with nothing moving in time
  • C) Shifts only the high frequencies out of phase
  • D) Slides the region earlier on the timeline
Answer **B.** Polarity is *which way is up*: positive pressure becomes negative, at all frequencies, instantly. Two states exist — normal and flipped. No time is involved, which is exactly why the button can't fix a timing problem. (A is the seductive wrong answer: "half a cycle" of *which* frequency? A fixed delay can't invert everything at once.)

9. Two captures of one source are offset by 1 ms. Which statement is true?

  • A) Every frequency is shifted by the same number of degrees
  • B) Each frequency is shifted by a different number of degrees — 1,000 Hz by a full cycle, 500 Hz by half a cycle, 250 Hz by a quarter
  • C) Only the low frequencies are affected
  • D) The offset is inaudible if both tracks are in tune
Answer **B.** Phase is *when*, measured per frequency in degrees of that frequency's own cycle — so one time offset creates a thousand different phase relationships. Sum the pair and some frequencies reinforce while others cancel: the comb. This is the core of the phase-versus-polarity distinction; if B didn't feel obvious, reread the sidebar.

10. Why can't the ∅ button fix a time offset between two captures?

  • A) It can, if you press it on the correct track
  • B) It inverts everything at once, so it exchanges the comb for the opposite comb — cancellations become reinforcements and vice versa — rather than removing the comb
  • C) It only works on stereo files
  • D) It adds latency to the track
Answer **B.** A time problem needs a time fix: slide the late track. The flip is a coin with exactly two faces; sometimes the swapped comb genuinely sounds better — which is why the flip test is a useful ten-second A/B — but the comb itself only disappears when the offset does.

11. The flip test asks you to sum to mono and keep whichever polarity state sounds:

  • A) Brighter
  • B) Louder
  • C) Fuller, especially in the low end
  • D) Wider
Answer **C.** Cancellation steals energy, most audibly from the lows, where wavelengths are long and the notches are broad — so the damaged state reads thin and the healthier state reads *full*. Mono, because summing forces the two signals to fully interact; stereo separation can hide interference that the mono world (phones, Bluetooth speakers, club PAs) will expose.

12. Each soloed mic sounds great; combined, the sound is thin, hollow, and smaller than either alone — and it gets uglier in mono. The diagnosis is:

  • A) A failing converter
  • B) Comb filtering from a time offset between the two captures
  • C) Too much preamp gain on one channel
  • D) Room modes
Answer **B.** That's the silent killer's exact signature: individually perfect tracks whose *sum* is damaged, because the same waveform arrived at different times and the offset notches the combined spectrum. The repair kit: flip test for the better comb, time alignment for the actual fix.

13. In the Glyn Johns method, the overhead and the floor-tom-side mic must be exactly equidistant from the snare's center so that:

  • A) Both mics receive equal level from the kick
  • B) The snare arrives at both mics at the same instant and stays solid and centered when the pair is panned apart
  • C) The cymbals stay quiet
  • D) The drummer can see both mics
Answer **B.** Equal distance means equal arrival time — the snare stays in phase with itself across the panned pair, so the backbeat sums solid, centered, and full. Break the law and the snare hollows out: the panned pair combs the kit's most important drum. The measuring tool is a piece of string, and it outranks every mic on the stand.

14. What does the 3:1 guideline actually accomplish?

  • A) It eliminates comb filtering between two mics
  • B) It keeps each mic's bleed quiet enough — roughly 10 dB down by inverse-square arithmetic — that the comb it digs is too shallow to hear
  • C) It aligns the phase of the two mics
  • D) It widens the stereo image
Answer **B.** The rule is for two mics on two *different* sources in one room, and it manages *level*, not physics: the interference still exists, but a much quieter copy digs notches you stop being able to hear. It's a guideline about making combs inaudible, not impossible — and it's not the tool for DI-plus-mic on one bass (that's the flip test and alignment).

15. You're recording a hardware synth on a 2-input interface. You record in stereo when:

  • A) The synth has two output jacks
  • B) The patch's identity actually lives in its left-right movement — wide pads, ping-pong delays, sounds that shimmer between the speakers
  • C) Always — stereo is higher quality
  • D) The song will be released in stereo
Answer **B.** Stereo when the width *is* the sound; mono when stereo is merely the default cable count. A centered bass patch or lead recorded mono saves an input, pans cleanly, and folds to mono without surprises. On a 2-input interface, a stereo capture spends your whole front panel — make it earn that.

True/False with Justification (5 × 2 points)

16. True or false: The ∅ switch on your preamp or DAW channel is a phase control.

Answer **False.** It's a polarity switch — a total, instantaneous inversion of the waveform at all frequencies, with two possible states and no time involved. Phase is a per-frequency time relationship; the label is fifty years of industry mislabeling. Vocabulary discipline: "flip the polarity," "align the timing."

17. True or false: Minimal drum micing is the budget compromise; properly recorded drums need a mic on every drum.

Answer **False.** Minimal micing is the *original* technique, not the discount version — nearly everything recorded before about 1970 used a handful of mics, and those drum sounds remain revered. The ear hears a kit, one instrument played by one human. More mics buy mix-time flexibility, not automatic professionalism — and every added mic brings phase homework with it.

18. True or false: When you blend a DI bass with a mic on the bass cab, your DAW's automatic latency compensation keeps the two signals aligned.

Answer **False.** Plugin delay compensation handles *plugin* latency — processing delay the software reports. The mic's lateness is acoustic: sound crawled through air at about a foot per millisecond between speaker and capsule, and the DAW has no idea that happened. That offset is yours to manage — flip test always, manual time alignment when the blend matters. (The all-software version — DI plus a sim'd duplicate — is the case where compensation genuinely covers the timing.)

19. True or false: When layering a room mic under a close mic, you should always slide the room mic into sample alignment with the close mic.

Answer **False.** Alignment is a choice with a flavor, not a repair with a receipt. Sliding a room mic fully forward erases the very lateness that made the room sound deep and *behind* the source. Close pairs — mic plus DI, top plus bottom — usually want full alignment; distance pairs want auditioning, aligned versus natural, level-matched, ears deciding.

20. True or false: If the acoustic guitar's strings are old and dull, a high-shelf boost at mix time will restore the missing sparkle.

Answer **False.** Dead strings don't attenuate high harmonics — the harmonics decay out of the worn metal and are never produced, so they're never captured. EQ can only boost what exists in the file; boost a shelf into that absence and you raise noise, pick clatter, and room, not shimmer. The fix costs a few dollars and must happen before the take: fresh strings, settled for a day or two. Capture is forever.

Short Answer (4 × 3 points)

21. Explain phase versus polarity in no more than five sentences — then give one scenario where the polarity flip is the complete fix, and one where only a time nudge will do.

Answer Polarity is which way is up: flipping it mirrors the whole waveform across zero, every frequency at once, instantly — two states, no time involved. Phase is *when*: the time relationship between two versions of a signal, measured per frequency, so a single fixed delay shifts every frequency by a different number of degrees. Summing a time-offset pair combs the spectrum; flipping polarity on one side exchanges that comb for its opposite rather than removing it. Flip-is-the-complete-fix scenario: something inverted at birth with no time offset — a miswired cable with pins 2 and 3 swapped, a top-and-bottom snare pair, an amp sim modeling an inverting circuit. Nudge-only scenario: a DI and a mic'd cab captured together — the mic's signal arrived late through air, and no inversion can un-delay it.

22. Walk the flip test, all five steps in order — then explain the physics behind "keep the fuller one."

Answer (1) Sum monitoring to mono. (2) Flip the polarity (∅) on one of the two tracks. (3) Listen with attention on the low end. (4) Keep whichever state sounds fuller — not brighter, not louder-seeming: fuller. (5) Return to stereo and carry on. The physics: when two captures interact, cancellation steals energy, and it steals most audibly from the lows, where wavelengths are long and the cancellation notches are broad. The flip presents you the two available combs; the one with healthier lows is the one losing less energy where it hurts most. Mono matters because it forces full interaction — and because the world folds your mix to mono without asking.

23. Give the three stacked reasons the DI is the first-call bass capture in a bedroom — then explain what "the player is a mic position" means, with two concrete examples.

Answer Reasons: (1) small rooms lie hardest below 200 Hz, and those standing-wave lies pour into any open mic permanently — the DI hears no room at all; (2) the DI's capture is full-range and consistent note to note, the clean low-frequency foundation the mix will lean on hardest; (3) a DI'd performance can be re-amped or sim'd into any tone, any era, forever — performance now, tone decision later. "The player is a mic position": half of bass tone is in the right hand, so producing the hand is placement work. Examples: plucking near the bridge is tight, burpy, and focused while near the neck is round and deep; fingers versus pick is a timbre decision bigger than most EQ moves. (Old strings versus new is a third honest answer.)

24. Scale the Glyn Johns method to a 2-input interface: name both honest configurations, what each sacrifices, and the one law that survives the scaling.

Answer Configuration one: overhead plus the floor-tom-side mic — the stereo kit picture with no kick spotlight; it works when the kick is healthy acoustically, and it sacrifices the anchored low-end emphasis. Configuration two: overhead plus kick mic — anchored low end, sacrificing the stereo width (a mono picture). Both commit balance at the source: the drummer's dynamics and the kit's tuning are the mix. The law that survives: any two mics that will be panned as a pair must be equidistant from the snare's center — measured with string or cable, not eyeballed — so the backbeat stays in phase with itself.

Applied Scenario (1 × 5 points)

25. Your cousin booked you for a weekend. Their bedroom-folk EP needs, in two days: acoustic guitar beds for five songs, one mic'd electric texture (an amp is available, but it's an apartment), bass on everything, banjo on two songs, and shaker plus tambourine. The lead vocals are already done. Gear: one LDC, one 57-class dynamic, a 2-input interface, amp sims in the DAW, blankets, string, painter's tape. Produce the plan: (a) the schedule order with an ears-budget argument; (b) the capture method per source — mic choice, starting position, or DI/sim decision; (c) every moment a flip test or alignment check is mandatory; (d) the hygiene ritual per block; (e) the width strategy for the acoustic beds on two inputs. Five defensible decisions, five points.

Answer (one strong solution — others earn full marks with justification) **(a) Schedule.** Day one morning: acoustic beds (the EP's foundation and the hardest *listening* work — placement verdicts want the freshest ears of the weekend). Day one afternoon: acoustic chorus doubles (same position, locked and logged from the morning — low decision cost), then the electric texture while daylight makes polite amp volume socially survivable. Day two morning: banjo (spiky transients need fresh ears for gain and placement calls). Day two afternoon: bass on all five songs (DI — low listening fatigue, high consistency value), then percussion last (the most forgiving capture of the weekend). One source per block: overdubbing is isolation by scheduling. Hard stop each evening with a mono safety listen and a backup. **(b) Captures.** Acoustic: LDC, twelfth fret, 8–12 in, slight tilt to the body, mono, facing the blanket-treated corner. Electric: 57 at the cap-edge seam, about an inch off the grille at conversation volume — *with the DI safety on input two* (the doctrine is non-negotiable), and painter's tape marking the keeper position. Bass: DI first-call into the instrument input, peaks near -10 dBFS set during the loudest section; if a song wants grind, duplicate the DI through an amp sim rather than re-mic — it's an apartment. Banjo: LDC 8–12 in, aimed near the neck-to-head seam rather than dead center of the head (the head is a drum — its center is the dust cap of this instrument), slightly off-axis to tame the pluck spike, gain-checked on the hardest hit. Shaker/tambourine: either mic, 6–12 in, off-axis, gain set for the transient. **(c) Phase checks.** Mandatory: any electric take where the DI and mic'd capture will be blended (flip test in mono, then sample-zoom alignment — the mic is late by the air gap); any DI-plus-sim bass blend (flip test — some sims invert polarity); the percussion *only* if two captures of one source ever happen. If the acoustic beds are ever doubled by a second simultaneous mic instead of a second pass: equidistance by string, then flip test anyway. **(d) Hygiene per block.** Tune before every take, not every session; fresh battery in anything active (the bass, any pickup preamp) at session start with spares in the bag; the noise-floor walk before the first take of each block (fridge, HVAC, laptop whine); phones to airplane mode and away from cables; wiggle-test cables before the block, not during the take; position photos and gain notes logged per source. **(e) Width.** Double-track the acoustic choruses — two full performances, same locked position, panned apart — rather than spending both inputs on a stereo pair. Two passes are genuinely different left versus right, fold to mono safely, and leave input two free for the DI safety all weekend. A stereo pair earns its complexity only if one of these songs turns out to be a solo-guitar feature; if that happens, XY first — it's the geometry that can't hurt you in mono. Bonus credit for scheduling the mono safety listen *daily* rather than once, and for noting that the banjo's gain must be set on the player's hardest attack, because banjo transients are where meters go to lie.

Scoring

Score Verdict
38–42 Ready. Phase and polarity live in different rooms of your head now — go record the instrument layers, and let the flip test be boring.
30–37 Solid. Most misses cluster in the phase-versus-polarity questions (8–11) or the Johns law (13) — reread the sidebar and the drums section, then run DAW Lab C1–C2.
21–29 The maps are loaded but the silent killer isn't feared yet. Reread "Multi-Mic Phase" and the sidebar, build the comb factory (C1) with your own hands, and retake this in two days — spaced, like the book taught you.
Below 21 The chapter deserves a second pass with the 🔄 checkpoints done honestly. Start with the source you actually own — read that section, record that source, then come back. The territory teaches the map.

Whatever you scored: C2's reflex drill is worth more than a perfect quiz. The quiz measures whether you know the ritual; the drill decides whether you'll run it at midnight with a session open.