Interviewer - Server > Architecture > Interview Service tier > Dialer Interface component > Playing audio files to respondents
 
Playing audio files to respondents
You can play sound recordings for a question or for a response within a categorical list. All playback facilities are under interviewer control and are specified in the interview script. See Playing sound files and recording responses for more information. When a question or response has a sound file associated with it, the page is displayed with a playback button bar at the appropriate place on the page (for responses, one button bar is displayed for each response with a sound file).
Activating a project does not copy audio files onto the dialer: you must copy sound files into the dialer's Audio folder manually. You can organize files by putting them in subfolders. The location of the Audio folder may vary between dialers, so consult the dialer’s documentation for advice.
The Export Data activity does not export sound files, and sound files are not available in any of the UNICOM Intelligence tabulation or analysis tools.
In UNICOM Intelligence 4.5, playback is supported on dialer extensions only and is only possible with the CATI (telephone interviewing) Player. When a dialer extension is not being used, the Play/Stop audio buttons are still displayed but selecting them does nothing except log an error indicating that the interviewer (or reviewer) has no audio capability.
If you are using UNICOM Intelligence Professional to test a script that uses audio files, you can display and answer the question but you cannot play the audio files.
Record and playback are not mutually exclusive: you can record a question that plays a sound file to respondents.
The dialer supports mono (single channel) .wav files in the following formats:
Sample rate
Sample encoding
Data rate
Comments
11025 Hz
8 bits/sample, PCM
38 MiB/h
Default file format
8000 Hz
16 bits/sample, PCM
55 MiB/h
Better sound quality
11025 Hz
16 bits/sample, PCM
76 MiB/h
Common file format
In this table, PCM stands for Pulse Code Modulation; 1 MiB is 1024×1024 bytes.
If you have stereo (two-channel) sound files you can convert them to mono format with a program such as WavePad.
See also
Dialer Interface component