How to make
good audio
recordings in
the field?
held January 2006 at the LSA meeting in
Albuquerque, New Mexico
Sven Grawunder
Max Planck Institute for evolutionary Anthropology,
Dep. of Linguistics, Leipzig, Germany
How to decide on what I
need? What is good?
Everybody will tell you: “It depends on…
 What do you want to do? What for?
 What is the field (recording) situation like?
 What can You handle?
 How big is your budget?
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Technology
Costs
Feasibility
Quality
Purpose
Field situation
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Costs
(technique,
transport)
Technology
(Microphone,
Recorder)
Recording Quality
(frequency range,
S/N ratio,
quantization )
Feasibility
(Power supply,
Know How)
Field situation
(recording
environment,
speaker)
Purpose
(documentation,
specific
elicitation)
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
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Goals (purpose)
Recorders
Microphones (incl. wind shield)
Setups
Field situation (recording environment)
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Analysis

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Transcription
Annotation
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Human hearing
(20-18000Hz)
Pitch
Intensity
Formant estimation
VOT
Voice Quality
Common practice in acoustic
phonetic analysis
(40-12000Hz)
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Why field recordings?

language
documentation (variety
of linguistic genres,
incl. musical genres)

conversational
analyses
oral history


specific elecitation of
paradigms for a
decent number of
speakers
(morphosyntax,
phonology, phonetics)



Wordlists
Narrative interview
Short stories
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Example 1
0.8599
0
-0.7548
34.0026
5000
0
34.0026
Time (s)
Time (s)
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48.0155
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Field situation

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Ambient noises (people, animals, natural
sources, vehicles, machines etc.)
Climate (temperature range, humidity)
Long Distances (Transport)
Energy supply
Interacting in foreign languages (working
language, contact language, elicited
language)
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Equipment
Recorders

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Analog/Digital (costs, formats, media)
Digital Formats (16bit PCM, 22.05kHz,
44.1kHz, 48kHz)
Quality (signal-to-noise ratio)
Power Supply (accumulator / battery)
Metering (details, delay, channel split)
Media (costs, durability, long-lasting)
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Barely acceptable to
acceptable
Barely acceptable (but
not recommendable)
 Micro cassettes via
Dictaphone
Acceptable (but not
recommendable)
 IPod
 PC/Mac Laptop
internal soundcard
 dv-camera tone (ext.
mic)
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Good to Very Good



Good (but not
recommendable)
Tape recorders
(analogue, DCC)
Very good
 DAT-Recorder
 Solid State Recorder
(Hi-)MD recorders
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DAT-Recorders
Fostex PD 4 MK II
Sony TCD-D100
TASCAM DA-P1
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solid state recorders
But:
•Power supply via Accu
•Price
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A good solution for the field?

e.g. Marantz PMD 660
 Battery powered
 Individual Channel
metering
 Mono recording possible
 44.1 & 48 kHz / 16bit
 Speakers + Line Out
 Professional XLR Input
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Not bad, but …

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It needs E-net connection for
direct USB-copying to PC/MAC
 card reader
Bad circuit insulation: phantom
power current influences the
recording Never run out of
batteries shielded cables, self
powered mics
Actual presets are invisible
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smaller siblings
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Saving Raw Data
To your computer
Via Card-Reader
or
Directly via USB-cable (Electricity needed
Another solution:
Direct Copying to a
“mobile photo hard drive”
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MD and Hi-MD

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ATRAC opaque format
ATRACWAV : Don’t betray yourself
MD-WAVMD-PC: Beware losing your
data
Still Open Software “needed”
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Microphones

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Frequency range
Frequency response
directionality
powering
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Microphone types
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built-in mics only in case of emergency!!!
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Dynamic mics

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bad quality
machine noise
omni directional
mic-mouth distance crucial
Self-powered electrets (condenser) mics

Rather than phantom powered condenser mics
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Frequency range
Frequency response
Directionality
•Omnidirectional (cartoid charcteristic)
•Directional (hyperbolic characteristic)
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Microphone stands

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On a tripod or stand?
On the table?
In your hand?
On the speaker?
Head mounted mic?
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21 / 02 / 06
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Mono or Stereo???
Mono
 Elicitation (One-toone)
 1 Speaker (+ close
standing interviewer)
Stereo
 More than 1 Speaker
 Moving Speakers
 Music
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Mono
AKG C100 S
Stereo
Shure Beta 53 B
Sony ECM-MS957
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windshields
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Don’t ignore…
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Phantom power (48 Hz)
Electric circuit (55-60 Hz)
Cable (kinks and adapters)
Cable shielding (microphone cable, NOT
monitor cable)
Connections (jacks, plugs etc.)
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Field conditions
The 7 enemies
of your
equipment

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Dust
Heat
Humidity / Water
Cold
Hard shaking/sudden
motion/vibration
Thieves
 Yourself

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Insolate your devices!
Watch the cables!
Keep the equipment
dry!
Protect your devices!!!
Watch or let watch!
Take save backups
with you!!!
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Some Rules 1 (Time)

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Have a time buffer  Expect that the
recording (setup) takes twice as long as in
the lab
Practice the record setup (microphone
settings, cable ports/jacks, recorder
settings)
Check “Recording Onset Time” (especially
for Tape-Recorders of all types: MC, DAT,
DCC)
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Some Rules 2 (Equipment)

Get to know your equipment before you go
to the field

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You don’t want to play with settings in a real
situation
Consider that the field session may be a
‘stressful’ situation
You need to focus on your subject (plus
Monitoring, Metering, Prompting paradigms,
Making notes, …)
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Some Rules 3 (Supply)

Make sure that you never run out of Power
(Batteries)!

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Accumulators
Solar panel for recharging?
Make sure that you never run out of
storage (Cassetes, Cards, etc.)!

Consider a ratio of 5:1
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Some Rules 4 (Field Situation)

Get aware of the recording environment

The more “natural” the more “distorted” –
Lower sometimes your expectations

Nonetheless try to control the recording
environment
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Recording environment

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Choose a possibly quiet location
Close doors and windows
Cover large reverberant surfaces
Ask for turning off lights, refrigerators, fans,
air conditioning etc.
Remove anything that ticks, buzzes, bangs,
rattles, squeaks, hisses, or otherwise
makes itself heard
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Speaker

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Find the appropriate Microphone – Mouth
distance (Headworn M. / Static M.)
Watch hands and feet
Ask for reiterations
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Some Rules 5 (After Recording)

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Control your data again – listen through
your recordings
Make notes (on settings, solutions, etc.)
Don’t lower the quality requirements for
digitization
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References:
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EMELD: http://emeld.org/school/toolroom/
DOBES: http://www.mpi.nl/DOBES
Oral history:
http://www.historicalvoices.org/oralhistory/
http://bartus.org/akustyk/signal_aquisition.p
df
Radio feature literature
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Good luck with your
recordings!!!
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How to make good audio recordings in the field?