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Making, Managing and Analysing Recordings of Interviews and Focus Groups. Duncan Branley Goldsmiths’ College, University of London 20 January 2005 duncan@gold.ac.uk. Contents. What do you want to do with your recordings? Recording and working with sound.
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Making, Managing and Analysing Recordings of Interviews and Focus Groups Duncan Branley Goldsmiths’ College, University of London20 January 2005duncan@gold.ac.uk
Contents • What do you want to do with your recordings? • Recording and working with sound. • Equipment for interviews and focus groups. • Transferring your recordings onto computer. • Improving your recordings. • Transcribing. • Moving transcriptions to NVivo. • Automatically coding for turn-takers in NVivo.
What do you want to do with your recordings? • In-depth, qualitative exploration - longer term. • Overview for commissioned research – short timeframe. • Archiving – formats and metadata. • Publishing on CD or the web • Quality – broadcast v research interviews.
What is sound? • Energy felt as vibrations. • Converted to electrical signal. • Heard or recorded. • Frequency – Pitch • Hertz (Hz) and kiloHertz (kHz) – waves/second. • Amplitude – volume • Human ear hears: • Range 16Hz - 20kHz • Range of normal speech 250Hz – 8kHz • Recorder’s frequency response (Images source: www.howstuffworks.com)
Analogue & Digital Recording • Analogue – exact replica - magnetic • Digital takes snapshots or ‘samples’ • Sampling rate/second • Sampling precision or resolution • Each block is one sample • Higher values match sound wave better • Channels: number of signals (Images source: www.howstuffworks.com)
Digital Recording and File Size • How many samples in 1 second? • CD: 44,100 – upper hearing range 20,000 Hz • Sampling precision: • 8 bit (256 possible values) or 16 bit (65,536) • 8 bits = 1 byte, 16 bits = 2 bytes • Channels: monaural (mono) or stereo • 1 minute of stereo sound at CD quality: • 44,100 samples/channel/second x 2 bytes/sample x 60 seconds x 2 channels = 10,584,000 bytes = 10,336 KB = 10.1 MB • mp3 and RealAudio – compression 1/10 – 1/14
Recording and Working with Sound • Sound converted: • From analogue to digital to record (ADC) • From digital to analogue to play (DAC) • Compressing digital audio files saves space: • Uncompressed: WAV (PC), AIFF (Mac) • Compressed: • Space: double highest frequency of source: • Speech: 250 Hz - 8,000 Hz =>16,000 or 22,050 • Telephone: 400 Hz - 3,400 Hz => 8,000 • See “Ready Reckoner”
Analogue and Digital Audio Compared • Sound quality • Not necessarily better – depends on sampling rate • Main problem with analogue recordings: hiss • Copies • Each analogue copy degrades, digital doesn’t. • Unless compress already compressed file. • Confidentiality – blanking identifiers • Storage • Media degradation v file format obsolescence
Recording Equipment (1) • Practice beforehand – only one go at interview • If disaster, write details of research encounter asap • Consumer products v professional • Easily replaceable supplies • Ubiquity may reduce alienation • ALL equipment should have: • Recording indicator • Ability to pause and resume easily • Mike-in connection • Line-in may not produce loud enough signal
Recording Equipment (2) • Cassette recorders • use at least Chrome CrO2 tape. • turning tape may be a distraction, but longer = lower quality • Dictaphones • Convenient but not too good quality – often mono • Minidisc • Longer recording time 74-80 mins + LP • Better quality recording – less mechanical noise • Microphone • External usually produces better results • Best if a microphone-in connection – if just line-in may not produce loud enough signal. • Lead rather than direct plug-in – lessens machine noise.
Preparing Before you Arrive • Check batteries or other power supply – and carry spares • Have spare media – unwrapped and labelled • Have a checklist of how to use the recorder • Carry the instruction book • Cassette recorders and dictaphones • Wind to beginning of recordable section
Preparing the Recording Environment • Sound from speaker – moves in all directions • Hard surfaces reflect – delay > echo • Soft furnishings, smaller room and in corner • Background noise • Ambient noise in room • Outside intrusions • You and your participants – moving, eating • Microphone • Position as close to interviewees as possible – best 30 cm – 1 m • If focus group, place in middle to pick up all sounds – stereo useful • Place on stand – naturalises, but beware vibrations • Check the recording level – although you may not be able to • This will amplify the signal from the microphone
Recording Telephone Interviews • Same advice – but some extra issues • Permission to record – ethical and legal • ‘Thinner’ recorded sound – frequencies 400 - 3,400 Hz only • Could record from handset/speaker, but not good quality. • Rather – RJ-11 connector – • As easy as connecting a computer to a modem • Position between telephone and handset – balanced signal • Telephone and line > your voice louder • Also may not work with advanced systems • Then connect recorder • Might want a Y splitter too – to use two recorders
During Interviews and Focus Groups • Concentrate on the interview! • Monitor the recorder from time to time to ensure that it’s still working.
After Interviews and Focus Groups • Don’t stop recording until interview is really finished • You may get some really interesting material towards the end • When finished prevent over-writing by disabling media • Minidiscs – slide the tab • Cassettes – click the tabs out • Label the recordings so that you know what’s on them later • May want to label using a system to preserve anonymity • Work it out in advance
Transferring your Recordings onto Computer • Connections: what’s making and what’s recording the sound? • Source: Line-out or Headphones/Speakers • PC soundcard: Line-in or Microphone • Set up sources using Windows Play Control • Set volume level on sound source. • Start recording on sound recording software • Audacity free to download and use. • May have own with eg soundcard or CD drive • Then start playing the source. • When play finished stop recording.
Connections (Images source: http://geraldtomyn.tripod.com/digan.htm) • Miniplug cable – 1/8 inch or 3.5 mm stereo (two rings) jack at each end • Carries Analogue only. • Source: Line-out or Headphones/Speakers • PC soundcard: Line-in (arrow into curves) or Microphone • Connect speakers to PC soundcard line-out to monitor sound.
Windows Volume and Recording Controls • If you’re not getting any sound this is the first thing to check • click on the volume button on the Windows toolbar • Recording: you can only have one source selected at a time. • The volume on both sides affects the loudness of the soundfile • If it is too loud, it will distort; too quiet, you won’t hear it. Test it.
Recording with Audacity • Start Audacity – creates a new ‘project’ • File | Preferences • Audio I/O – make sure it’s the same as the Volume controls – probably your soundcard’s name. • Quality: Sample rate: 22,050 Hz format: 16 bit – don’t need CD quality • File format: WAV (Microsoft 16 bit) • File | Save As – give it a name • Click the circular red record button • Start playing the source • When finished click the yellow square stop button • File | Save • To use in other programs you need to export the file • File | Export as either WAV (full quality) or mp3 (slightly lower, but smaller file size).
Improving your Recordings in Audacity • Have created a WAV (PC) or AIFF (Mac) file. • Keep as original – work with a copy. • Could compress: mp3 – fine for speech. • Can work with parts of file (drag to select): • Make quiet parts louder. • Effect | Amplify – accept default suggestion • Blank identifying information (possibly after transcription) • Click on silence button (wave with flat line in middle). • Remove hiss – find hiss with no words – be careful • Effect | Noise Removal – 2 steps • Save brief extracts as separate files • File | Export extract as… • Remember to save your copy file.
Transcribing • Do you need complete transcriptions? • Summaries in Word or NVivo (with labelled proxy document) – partial transcription. • Useful first step – in field and for familiarisation • Transcribe cassettes in full: foot-pedal control or auto-rewind • Use Transcriber to tie your transcription to the sound files clause by clause – cp sub-titles. • Can export to NVivo or a webpage. • Transcription not neutral – part of your analysis.
Transcriber • This enables you to create your transcriptions while following your sound files on screen. • Start Transcriber and open an audio file – WAV or mp3 • Click on the play button and you’ll hear it. • When there’s a pause, press Enter and you’ll create a ‘segment break’ • When finished select Signal | Playback Mode | Loop on Segment – this enables you to replay each segment while you’re transcribing it. Press Tab to stop and start it and the up and down arrows to move between segments. • When finished set back to continuous playback. • To create a new speaker: Segmentation | Create turn or Crtl-T • You can double click to enter the full identifier. • When finished save – and can export to html or NVivo format.
Moving Transcriptions to NVivo • From Transcriber • Must ensure have NVivoTxt.tcl installed inC:\Program Files\DGA & LDC\Transcriber\converter • File | Export | Export to NVivo Plain Text format. • This will create a plain text file with the same name as the soundfile you are working on – except with a .txt ending. • In NVivo Create a new document by importing this file – using the 'Read marked-up title and description paragraphs' option.
Automatically Coding in NVivo • Document formatted with Heading styles. • NVivo can see structure. • NVivo can use this to code for each turn-taker. • Can use for structured, semi-structured and unstructured interviews.
More Information • Duncan Branley (2004) ‘Making and Managing Audio Recordings’ in Clive Seale (ed) Researching Society and Culture (2nd edition): Sage, London pp 207-228. • If you have further questions, email duncan@gold.ac.uk