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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?. - PowerPoint PPT Presentation
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How to make good audio
recordings in the field?
held January 2006 at the LSA meeting in Albuquerque, New Mexico
Sven GrawunderMax Planck Institute for evolutionary Anthropology,
Dep. of Linguistics, Leipzig, Germany
S. Grawunder MPI EVA Leipzig 2
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?
S. Grawunder MPI EVA Leipzig 3
Technology
Purpose
Quality
Field situation
Feasibility
Costs
S. Grawunder MPI EVA Leipzig 4
Costs (technique,
transport)
Feasibility(Power supply,
Know How)
Purpose(documentation,
specific elicitation)
Recording Quality (frequency range,
S/N ratio, quantization )
Technology (Microphone,
Recorder)
Field situation (recording
environment, speaker)
S. Grawunder MPI EVA Leipzig 5
Goals (purpose) Recorders Microphones (incl. wind shield) Setups Field situation (recording environment)
S. Grawunder MPI EVA Leipzig 6
Analysis Transcription Annotation
Human hearing (20-18000Hz)
Pitch Intensity Formant estimation VOT Voice Quality
Common practice in acoustic phonetic analysis (40-12000Hz)
S. Grawunder MPI EVA Leipzig 7
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
S. Grawunder MPI EVA Leipzig 9
Example 1
Time (s)34.0026 48.0155
-0.7548
0.8599
0
Time (s)34.0026 48.0155
0
5000
S. Grawunder MPI EVA Leipzig 10
Field situation 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)
Equipment
S. Grawunder MPI EVA Leipzig 12
Recorders 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)
S. Grawunder MPI EVA Leipzig 13
Barely acceptable to acceptable
Acceptable (but not recommendable)
IPod PC/Mac Laptop
internal soundcard dv-camera tone (ext.
mic)
Barely acceptable (but not recommendable)
Micro cassettes via Dictaphone
S. Grawunder MPI EVA Leipzig 14
Good to Very Good Good (but not
recommendable) Tape recorders
(analogue, DCC)
(Hi-)MD recorders
Very good DAT-Recorder Solid State Recorder
S. Grawunder MPI EVA Leipzig 15
DAT-Recorders
Sony TCD-D100
TASCAM DA-P1
Fostex PD 4 MK II
S. Grawunder MPI EVA Leipzig 16
solid state recorders
But: •Power supply via Accu•Price
S. Grawunder MPI EVA Leipzig 17
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
S. Grawunder MPI EVA Leipzig 18
Not bad, but …
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
S. Grawunder MPI EVA Leipzig 19
smaller siblings
S. Grawunder MPI EVA Leipzig 20
Saving Raw DataTo your computer Via Card-Reader orDirectly via USB-cable (Electricity needed!!!)
Another solution:Direct Copying to a “mobile photo hard drive”
S. Grawunder MPI EVA Leipzig 21
MD and Hi-MD ATRAC opaque format ATRACWAV : Don’t betray yourself MD-WAVMD-PC: Beware losing your
data Still Open Software “needed”
S. Grawunder MPI EVA Leipzig 22
Microphones Frequency range Frequency response directionality powering
S. Grawunder MPI EVA Leipzig 23
Microphone types built-in mics only in case of emergency!!!
bad quality machine noise omni directional
Dynamic mics mic-mouth distance crucial
Self-powered electrets (condenser) mics Rather than phantom powered condenser mics
S. Grawunder MPI EVA Leipzig 24
Frequency responseFrequency range
Directionality
•Omnidirectional (cartoid charcteristic)•Directional (hyperbolic characteristic)
S. Grawunder MPI EVA Leipzig 25
Microphone stands On a tripod or stand? On the table? In your hand? On the speaker? Head mounted mic?
S. Grawunder MPI EVA Leipzig 26
21 / 02 / 06
S. Grawunder MPI EVA Leipzig 27
Mono or Stereo???Mono Elicitation (One-to-
one) 1 Speaker (+ close
standing interviewer)
Stereo More than 1 Speaker Moving Speakers Music
S. Grawunder MPI EVA Leipzig 28
AKG C100 S
Sony ECM-MS957
StereoMono
Shure Beta 53 B
S. Grawunder MPI EVA Leipzig 29
windshields
S. Grawunder MPI EVA Leipzig 30
Don’t ignore… Phantom power (48 Hz) Electric circuit (55-60 Hz) Cable (kinks and adapters) Cable shielding (microphone cable, NOT
monitor cable) Connections (jacks, plugs etc.)
Field conditions
S. Grawunder MPI EVA Leipzig 32
The 7 enemies of your equipment Dust Heat Humidity / Water Cold Hard shaking/sudden
motion/vibration Thieves
Yourself
Insolate your devices! Watch the cables! Keep the equipment
dry!
Protect your devices!!! Watch or let watch! Take save backups
with you!!!
S. Grawunder MPI EVA Leipzig 33
Some Rules 1 (Time) 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)
S. Grawunder MPI EVA Leipzig 34
Some Rules 2 (Equipment) Get to know your equipment before you go
to the field 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, …)
S. Grawunder MPI EVA Leipzig 35
Some Rules 3 (Supply) Make sure that you never run out of Power
(Batteries)! Accumulators Solar panel for recharging?
Make sure that you never run out of storage (Cassetes, Cards, etc.)! Consider a ratio of 5:1
S. Grawunder MPI EVA Leipzig 36
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
S. Grawunder MPI EVA Leipzig 37
Recording environment 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
S. Grawunder MPI EVA Leipzig 38
Speaker Find the appropriate Microphone – Mouth
distance (Headworn M. / Static M.) Watch hands and feet Ask for reiterations
S. Grawunder MPI EVA Leipzig 39
Some Rules 5 (After Recording) Control your data again – listen through
your recordings Make notes (on settings, solutions, etc.) Don’t lower the quality requirements for
digitization
S. Grawunder MPI EVA Leipzig 40
References: 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.pdf Radio feature literature
S. Grawunder MPI EVA Leipzig 41
Good luck with your recordings!!!