Acoustic guitar
- Range
- E2–E6
- Overtones to
- about 2.1 kHz
- Peaks up close
- up to 94 dB SPL
- Sources
- 105 independent: not from a mic maker
Range
E2 to about E682.4 Hz – 1.32 kHz
Standard tuning E2 A2 D3 G3 B3 E4; notated an octave above sounding. Top note depends on frets: B5 (19, classical), C6 (20, most acoustics), D6-E6 (22-24, electric).
| Low strings | E2–F#3 | full, boomy; wound strings |
|---|---|---|
| Middle | G3–D#4 | warm |
| High | E4–E6 | bright; thin high up the neck |
Boundaries follow the open strings (E2-D3 wound, G3 up plain on steel-string); an estimate, not a standard division.
Overtones reach about 2.1 kHz (the highest harmonic within 40 dB of the strongest, at a moderate level; louder playing reaches higher)11.
The sound
A plucked string starts with many harmonics, which die away faster than the fundamental; where along the string it is plucked sets which harmonics are weak.
Where the sound goes
Not a point source. Panels and the air cavity both radiate; the air resonance is around 100 Hz and booms if a close mic sits on-axis with the sound hole; the body and air resonances carry further than the string and pick noise, and high frequencies from the strings are shadowed by the player's arm and body (Senior). DPA: "many sound sources on the acoustic guitar".9,1
Playing techniques
- Pick vs fingers: a pick is brighter, with a sharper attack
- Plucking position: near the bridge thinner and brighter, over the neck rounder
- Palm mute: short and thuddy
- Harmonics: pure, bell-like
Frequency areas
How loud
Sound pressure level measurements as published. Different kinds of figure (a playing level, a peak, a dose at the player's ear) can't be compared with each other, and neither can figures at different distances.
| Playing level | |
|---|---|
| 80–90 dB | at 1 m; acoustic guitar secondary12 |
| Peaks | |
| 90–94 dB | about 0.45-0.6 m from the guitar; Forum readings with phone dB-meter apps: classical guitars 'capable of producing sound in the 90dB range' at 2 ft / 450 mm (A major chord, harmonics, Lagrima); peaks over 92 dB, possibly 94 dB, plucking open strings hard at about 45 cm (converted resonator guitar)13 |
| Sound power | |
| 59–88 dB(Z) | sound power level Lw (dB re 1 pW), not a sound pressure at a distance; Modern guitar, single notes over the whole range played as soft and as loud as possible by a professional Berlin player, anechoic chamber TU Berlin, 32-mic spherical array; FAST time weighting for the plucked transients14 |
A modern guitar's sound power runs from 59 to 88 dB (TU Berlin anechoic measurement, single notes pp to ff). Classical-guitar forum players read 90-94 dB peaks on phone meters at about 0.5 m, and a hearing-protection page gives 80-90 dB at 1 m (secondary).
Recording it
Sound On Sound's engineers split between a few inches (Bob Bullock, Frank Filipetti) and two to three feet (Steve Albini, Jim Scott), with omnis for close work (Keith Olsen) and an X-Y pair off the 12th fret (Chuck Ainlay, Bob Bullock 4-6 in apart). Large-diaphragm condenser at the bridge plus a small-diaphragm at the 12th fret is the common two-mic split. MusicRadar warns that side-address large diaphragms are hard to aim.9,5,3
Mics
- 28 setups from 10 sources, 5 of them independent of any mic maker.
- On top: the mics more than one source names for this instrument, in any role, the most named first. That is a count of sources, not our verdict.
- In the full list, each mic shows how many sources name it for that role, and how many of those come from a mic maker.
- Shure SM57 3 sources, 1 from a mic makerClose, named, no placement given
- Shure SM81 3 sources, 2 from mic makersClose, named, no placement given
- Aston Origin 2 sourcesClose
All the mics sources name, by setting and role (39)
On stage
Clip-on
- DPA 4099 CORE+1 source from its own maker
Named, no placement given
- Shure Beta 57A1 source from its own maker
- Shure KSM1091 source from its own maker
- Shure KSM1371 source from its own maker
- Shure KSM1411 source from its own maker
- Shure KSM271 source from its own maker
- Shure KSM321 source from its own maker
- Shure KSM441 source from its own maker
- Shure PG571 source from its own maker
- Shure PG811 source from its own maker
- Shure SM571 source from its own maker
- Shure SM811 source from its own maker
The 3 setups behind this: placement and quotes
- Clip-on DPA 4099 CORE+clip-on, GC4099 guitar clip (guitar clip)
Directional 4099 CORE+ or 4011ES focuses on the instrument and isolates it from other sources (paraphrase).
1 - Clip-on condenser, miniature (miniature mic clipped outside the sound hole)clip-on, stage
Miniature microphone clipped outside sound hole: natural, well-balanced; good isolation.
2 - Named, no placement given Shure KSM141 or Shure KSM137 or Shure KSM109 or Shure KSM44 or Shure KSM32 or Shure KSM27 or Shure SM81 or Shure Beta 57A or Shure SM57 or Shure PG81 or Shure PG57listed for acoustic guitar
Listed under "Acoustic Guitar" in the Shure Microphone Selection Guide (no argument given).
2
Studio and stage
Close
- DPA 4006ES (earlier version of the DPA 4006A)1 source from its own maker
- DPA 4011ES (earlier version of the DPA 4011A)1 source from its own maker
- DPA 40611 source from its own maker
- Shure PGA811 source from its own maker
- Shure SM571 source
- Shure SM812 sources, 1 from its own maker
The 6 setups behind this: placement and quotes
- Close DPA 4011ES (earlier version of the DPA 4011A)close
Directional 4099 CORE+ or 4011ES focuses on the instrument and isolates it from other sources (paraphrase).
1 - Close DPA 4006ES (earlier version of the DPA 4006A) or DPA 4061close, gooseneck
An omni like the 4006ES or 4061 can sit close without proximity-effect bass loss (paraphrase).
1 - Close Shure SM81close, 12th fret
"The Shure SM81 is an iconic mic for recording acoustic guitar that's proved itself over decades." (its pick 1)
3 - Close Shure SM57close, strummed parts
Pick 4 in MusicRadar; a dynamic suits "a strident strummer", rejecting handling noise (paraphrase).
3 - Close Shure SM81close
SM81 is the first of two "Recommended Acoustic Guitar Microphones" on Shure's page.
4 - Close Shure PGA81close, budget
PGA81 is the second of two "Recommended Acoustic Guitar Microphones" on Shure's page.
4
Studio
Close
- AKG C451 B1 source
- Aston Origin2 sources
- Audio-Technica AT20201 source
- Audio-Technica AT50451 source
- Beyerdynamic M 1601 source
- Neumann KM 1841 source
- Neumann TLM 1021 source
- Neumann U 47 FET1 source
- Rode M31 source
- Rode NT1 Signature1 source from its own maker
- Rode NTR1 source
- Royer R-122 MKII1 source from its own maker
- sE Electronics sE51 source
- sE Electronics Voodoo VR21 source
- Sennheiser MK 81 source
- Shure PGA271 source
- Shure SM571 source
- Sontronics Aria1 source
Stereo pair
Main pair or array
- Aston Starlight1 source
- Audio-Technica AT40211 source
- Audio-Technica AT40501 source
- Rode NT41 source
- Rode NT51 source from its own maker
Stereo pairX-Y
The 19 setups behind this: placement and quotes
- Close 2 × Neumann KM 184close or pair, 12th fret
"If money is no object... an Octo Set of Neumann KM184s"; KM184 stereo set is its pick 3 for acoustic guitar.
3 - Close 2 × Beyerdynamic M 160 or AKG C451 Bclose or pair
Listed as pick 2 in MusicRadar's best acoustic guitar mics. ... Pick 6 in MusicRadar's best acoustic guitar mics.
3 - Close sE Electronics Voodoo VR2close, studio
Pick 5 in MusicRadar's best acoustic guitar mics.
3 - Close Rode M3 or Aston Originclose, budget
Pick 7: a "quality condenser mic... at a price point more suited to a good dynamic mic". ... Pick 8 in MusicRadar's best acoustic guitar mics.
3 - Close Aston Origin or Audio-Technica AT5045 or Neumann U 47 FET or Rode NTR or Sontronics Aria or Neumann TLM 102close
MusicTech recommendation: "On guitars, it sounded instantly usable." ... "Excels on acoustic instruments and vocals and is an outstanding all-round instrument recording mic option." ... "Using the Neumann individual notes in a chord were easy to distinguish." ... "Recording acoustic instruments presents no difficulties." ... "Impressive detail resolution for capturing delicate acoustic-guitar picking." ... "One of Neumann's own recommendations for recording acoustic guitar."
5 - Main pair or array 2 × Aston Starlightsingle or stereo pair
"Bright and lively. The bottom end was present, but not flabby."
5 - Close 2 × sE Electronics sE5pair
"The sE5s captured plenty of detail, presenting a natural-sounding guitar with plenty of body and detail."
5 - Close Sennheiser MK 8close or stereo
"Ably held its own against more expensive makes."
5 - Close Audio-Technica AT2020 or Shure PGA27close, budget
"A very impressive and flexible mic for the price." ... "One of Shure's own recommendations, specific to acoustic guitar."
5 - Main pair or array Rode NT4stereo pair
"An easy and relatively cheap way to get a great stereo recording."
5 - Main pair or array 2 × Audio-Technica AT4021stereo pair
Tutorial used a pair of AT4021s for stereo configurations.
6 - Main pair or array 2 × Audio-Technica AT4050stereo pair or mono
Tutorial used a pair of AT4050s for stereo and an AT4050 for a mono position.
6 - Close Shure SM57mono, neck position, aggressive parts
"Sometimes, a condenser microphone is not the most appropriate choice"; a Shure SM57 used at the neck position for aggressive rhythm parts.
6 - Close Rode NT1 Signaturemono, 12th fret
"We recommend a large-diaphragm condenser like the NT1 Signature Series for a rich, detailed sound" (single-mic technique).
7 - Main pair or array 2 × Rode NT5stereo pair, X-Y or spaced (matched pair)
For two-mic techniques: ideally small-diaphragm condensers such as the NT5 (available as a matched pair).
7 - Close Royer R-122 MKIIclose, 8-12 in off the 12th fret (backward)
"When single miking an acoustic guitar, a great position is 8 to 12 inches off the 12th fret, with the mic aimed at the soundhole."
8 - Close omni (omni, close)close, no proximity effect
Keith Olsen: "Acoustic guitar sounds terrible with a cardioid mic too close to it"; he suggests an omni.
9 - Main pair or array 2 × condenser, cardioid, X-Y pair (crossed cardioid pair near the 12th fret)stereo pair, off the 12th fret
Chuck Ainlay uses X-Y, one capsule at the fretboard, one at the hole, off the 12th fret; Bob Bullock 4-6 in.
9 - Distant 2 × Oktava MK-012spaced pair, about 4 ft up, guitar duo (omni pair)
Cheap small-diaphragm omnis used as a spaced pair to record two guitarists; "remarkably good" result (paraphrase).
10
Sources
- DPA Mic University: How to mic an acoustic guitar
- Shure: Microphone Techniques for Live Sound Reinforcement
- MusicRadar: Best acoustic guitar mics
- Shure: How to Choose the Best Mics for the Guitar
- MusicTech: The Ultimate Guide To Recording Everything - Acoustic Instruments (2017)
- Production Expert (Audient): 5 Essential Tips For Recording Acoustic Guitar
- Rode: Three Simple Techniques for Recording Better Acoustic Guitar
- Royer Labs: Recording Acoustic Guitar, Violin, Ukulele, Cello & Other Stringed Instruments
- Sound On Sound: How To Record A Great Acoustic Guitar Sound (Mike Senior, 2010)
- Sound On Sound: Session Notes - Recording Acoustic Guitars (Mike Senior)
- University of Iowa Electronic Music Studios, Musical Instrument Samples (steel-string guitar), as trimmed/normalised in tonejs-instruments; own FFT analysis
- Bollsen: Earplugs for Guitarists
- Classical Guitar Delcamp forum: guitar loudness measurements thread (2020)
- JASA: Sound power and timbre as cues for the dynamic strength of orchestral instruments (Weinzierl, Lepa, Schultz, Detzner, von Coler, Behler)
- iZotope: EQ Cheat Sheet
- Sonicbids: EQ Cheat Sheet, Mixing Frequencies for Every Instrument