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24 Things to Remember Digital Media for Linguists Part 1 15th June 2016 Tom Castle
The areas of audio technology use: • • • • • • • • •
Live performance (arts & entertainment) Film & TV (arts & entertainment) Music (arts & entertainment) Architectural acoustics (scientific) Surveillance (scientific) Ornithology (scientific) Radio (entertainment & communication) Internet (entertainment & communication) Linguistics (?)
The areas of audio technology use: • In arts & entertaiment, audio is used to create pleasing (aesthetic) effect often constructed, fake experiences (mixed, filtered, distorted & augmented sounds). • In research, science and archiving, recordings are carefully controlled, perhaps calibrated, not filtered, not made easy to listen to …
Audio & Video for Linguists
Audio & Video for Linguists
• Recordings for language documentation are expected to be scientific records of the language as it was spoken.
• Here is the snag. The problem is that for revitalisation projects the linguist's minimum standard recordings may not be enough. If a radio station wants to use your recordings they will want to edit them, perhaps remove noise. For dictionaries we need consistency. For TV documentaries hours of static shots of linguist's video would be considered boring.
• This scientific approach applies to both audio and video. Video recordings of conversations can be just a static shot. We see gesture and the relationship between the people speaking. We can see and hear what we need to see and hear. • Here we realise that there are minimum standards for our recordings we need to understand what these are and what it takes to make this type of recording.
• If part of your re vitalisation project is to produce compelling TV style video materials you will have to employ TV programme makers which might be enormously expensive. Alternately you could find focussed and thorough video training to learn in detail about effective media skills the same applies for phone apps, CD Roms, publishing etc...
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Digital media skills for fieldwork researchers
Recording Technologies used • Still Photography • Audio recording • Video recording Three separate previously analogue technologies with different histories, equipment development, techniques and skills acquisition
Applied technologies • Language documenters will be using these technical tools (recorders, cameras …). • To become skillful they will need to practice with the equipment. • Discussing the nature and quality of recordings helps develop a fuller understanding of which methods produce better results. • These technologies have history, culture and vocabulary of their own. It is best if we learn from these – not invent something of our own. • Initially, to develop confidence in using these skills, discuss and evaluate the recordings rather than the language content!
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What do you need to know? What do you need to learn about – in order to produce good media documentation? • What is a good photgraph? • What is a bad photograph?
Still Photography To create a clear picture we need … • control over focus – large lens • control over exposure – a shutter and an iris • control over framing – using focal length, choice of lenses • control over shaking – tripod or fast shutter speed In discussing photographs we can comment that it is … • “the background is OK but his face is out of focus” • “too dark, under exposed” • “badly framed, we can’t see his legs!” • “it is all blurred, it must be camera shake”
What do you need to know? What do you need to learn about – in order to produce good media documentation?
Audio recording To create a clear recording we need … z
What is a good audio recording?
z z
What is a bad audio recording?
z
control over input volume – dial, knob, switch control over unwanted noise – the type of microphone control over clarity – recording with non reflective walls control over picking up user noise – using a ‘mic stand’
In discussing recordings we can comment … z
What do you need to know? What do you need to learn about – in order to produce good media documentation?
What is a good video? What is a bad video?
“… it is distorted, over recorded, it is clipping”
z
“We can hear the chickens! Use a more directional microphone” “… too much reverberation, is difficult to make out the words”
z
“He’s tired of holding the microphone, hear the handling noise”
z
Video recording To create a clear visual recording we need … • control over framing – careful use of zoom and camera height • control over camera shake – careful use of tripod • control over auto functions – switch off functions not required • control over colour – before each session set the white balance In discussing video recordings we can comment … • “I wish it would stay still – there’s a lot of zooming in and out” • “He’s shot it hand held, I wish he had used a tripod” • “It keeps changing focus, that’s the trouble with auto focus” • “The shots inside are green, they didn’t set the white balance”
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Culture and Vocabulary I am suggesting that trainees should immerse themselves in the culture of recording making throughout their early training as linguists. They should be able to discuss the quality of their field recordings with each other in the appropriate professional language, also about techniques and methods used. The more thorough the grounding in this culture, the more likely specific solutions can be developed through experimentation, for particular projects with innovative methods, obtaining better, clearer recordings. I also suggest sharing this culture with your 'subjects', people you are recording like to know whether their efforts are successfully recorded and some people within the community will naturally want to pickup skills of their own, making recordings themselves when researchers go home.
Audio Of all the media I have mentioned the most important for linguists is audio. Even if using video – the quality of the audio part of the recording will determine the usefulness and quality of the complete recording. At this Summer School I will be concentrating on helping you appreciate the truth of the two statements above. We will look at making good audio recordings and listening to and talking about them.
Microphones
Microphones and audio quality Microphones are the greatest determinant of audio recording quality • selection of appropriate microphone(s) for the task • placement and handling of the microphone(s)
Microphone physical principles • dynamic generate signal from sound pressure more robust, less accurate used for musical and live performance • condenser more fragile, sensitive and accurate need power source battery or phantom power in general, use condenser microphones for language documentation
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Omni
Microphone directionality omni
• lavalier or tie clip microphones are typically omni directional
omni directional
Microphone directionality cardioid
Cardioid • many standard handheld microphones are cardioid microphones
cardioid
Shotgun Microphones
Microphone directionality shotgun
• shotguns are good for quiet sources, in noisy environments, and for video work
shotgun/directional/hypercardioid
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Stereo microphones Spatial information is an essential part of audio which can be provided by a so called stereo microphone. In fact it is two matched microphones on one stick
Stereo microphones
ORTF & Binaural
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Microphone placement • where should the microphone be? • in general, about 20cm from the speaker’s mouth
Reduce background noise Signal Noise
the speaker’s voice the speaker’s chickens
Increase the signal and decrease noise by: • placing the microphone as close as possible to the signal source • placing the microphone as far as possible from the noise source
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Different Recording Genres
Advantages of recording in stereo • A stereo recording is two mono recordings of the same event
• Recordings for phonetics study one microphone close to the speaker, important to reduce background noise • Two people in conversation or a stereo microphone
two microphones
• One recording for one ear and one for the other ear • Humans have interpreted the difference between one ear’s experience of sound and the other’s as an awareness of hearing where a sound comes from • This can be referred to as 'psychoacoustics'
• Solo or group performance or ORTF/binaural
stereo microphone
• Soundscapes
ORTF & binaural
• We have learned to use this spatial information all our lives • When you listen to a recording in stereo, you can concentrate on what you want to listen to – and ignore the noise • What is a babble in mono – can be a conversation in stereo
Microphone Stands Microphones pick up noise from handling and from things that are in contact with them. Use some sort of 'Mic Stand' where possible!
Remember the shotgun? ... it has a sensitivity where you might usually think to handle it … z
Train to keep very still
z
Use a suspended holder
z
Use a boom of stand
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Wind shields Most microphones come with a foam “Wind shield”. As with a “Pop shield” they are designed to eliminate plosives or “pops”.
They also stop the microphone collecting moisture from speakers mouths!
Wind gags
Wind shields are NOT wind gags! Wind gags stop the sound of breezes and wind creating destructive lower frequencies in your recordings. Dead cats, dead spiders and dead wombats ...
Wind gags Dead cats Dead spiders Dead wombats
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Input level control
Input level control Every recording device has some method of controlling how high your microphone's signal is recorded. You have to adjust the “Input level” so the signal is high enough to hear the sounds clearly but not over recorded so that it distorts. This distortion is called “clipping” and should be avoided.
Input level control
Input level control While you are recording you can hear the distortion.
If you look at the wave form in an audio editor, you can see clipping.
There are also indicators to let you know it is happening. So, avoid going “into the red”
Monitoring
Monitoring
Use headphones to check the quality of your recordings.
Make sure you have located the headphone level control and set the volume to a comfortable level.
Is the level right?
Note: NOT THE SAME as the Input level!
Is there system noise? Can you hear distortion?
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Power
Power
Most dedicated audio recorders can be operated either with mains power or with batteries.
Some audio recorders can supply “Phantom Power” to microphones through XLR cables. This means that the microphone need not have its own battery.
Experience tells us that there is less chance of electrical interference using batteries rather than mains.
Phantom power tends to mean the recorders batteries are used up faster!
Power
Storage
Your recorder's use of batteries can be calculated and therefore can be predicted.
Make sure you understand how many recordings can fit on your storage cards.
Make sure you have enough for your project.
Stereo recordings are twice as big as mono!
Remember your microphones will need batteries aswell.
Storage
Storage
You might decide to re use your flash cards and transfer them to a hard drive.
Locate cheap deals on small value flash cards (8GB, 16GB) buy loads of them …
This is not back up! Make sure you keep MORE THAN ONE version of each recording.
AND KEEP THEM!
Use a different carrier: CD, DVD, 'Cloud' or USB stick
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Settings Most audio recorders require you to use a menu so you get what you want. You have to find out how to change these settings. 1) Internal Microphones or External Microphone connections 2) Mono or Stereo
Settings
3) .Wav or .MP3 [set to .Wav!] MP3s are a compressed file format and are “lossy”. Record in WAV format for academic work. 44.1 khz 16 bit is good enough!
Settings 4) Set AGC to off “Automatic Gain Control”, whilst it will give you clip free recordings it is unnatural and will record all background sounds at a high level in gaps between spoken words. Set the input levels manually – keep control ...
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XLR
XLR v. Mini jack Traditional Professional versus Miniature Audio
XLR • rugged • pro microphone compatible • lo noise
Mini Jack • light weight • phone and video compatible • cheap
• the physical connection is independent of the electrical connection • transmits phantom power • low noise over long cable runs • you can use XML to mini jack cables or converters for recorders with mini jack inputs
Division in the market! Difficult choices!
Digital Audio Recorders
Versatile tablets & phones
• XLR or Mini jack or both?
• Connectivity
• Ruggedness and build
• Ruggedness & build
• Accuracy
• Accuracy
• Media type
• Media type
• Battery life
• Battery life
• Cost
• Cost
Merging technologies • Still photography cameras • Video cameras • Go Pro cameras • Beech Tek • Interfaces • XLR – again!
Merging technologies • Video cameras can take still photographs and, with external microphones; make good audio recordings • Still cameras can produce good quality short video, some with sound • Audio recorders can produce different versions of the same recording (hi & lo) like “bracketing” in photography
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Metadata Keep detailed information about your recordings. Metadata is data about your data. Use spreadsheets to list different categories of information. Who, when, where, what & how … Including – which microphone!
Listening
Listening and Evaluating • Are there obvious faults? • Does the recording achieve the goals set at the start? • Is it easy to listen to? • What could be done next time to improve the quality? • Is it fit for purpose?
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Audio minimum Eight points for good audio recording 1. Choose the correct type of microphone 2. Use a microphone stand (“mike stand”) 3. Use a wind gag outside (“dead cat”) 4. Do not use auto gain (AGC) 5. Record in uncompressed format “wav” 6. Have spare recording cards and batteries 7. Don’t let your recordings “clip” 8. Monitor your recording
Video Minimum Eight points for good video recording 1. Frame the speaker with space for gesture 2. Light should generally come from behind the camera 3. If you are out side, use a wind gag 4. Set the white balance 5. Use a tri pod 6. Focus by hand once, do not to use auto focus 7. Have spare recording cards and batteries 8. Monitor your recording
Still Photography Minimum Eight points for taking good photographs 1. Frame the shot with zoom and your position 2. Light should generally come from behind the camera 3. Set the exposure correctly or use flash 4. Set the white balance 5. Use a tri pod 6. Focus by hand once, or use zone focus 7. Have spare recording cards and batteries 8. Inspect/check your pictures in the camera
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