Audio specific recommendations
The following audio specific recommendations are available in the page below:
- File format
- Audio file size
- Volume level
- Splitting up your audio file into smaller pieces
- Cleaning up your recording
- Converting your audio file
File format
When adding an audio file to your Learning Room using the Adding from a computer method it is important to consider what file format the audio recording is in.
The MP3 file format is most appropriate as it will play back regardless of what computer you have and the software that is installed. The WMA (Windows Media Audio) file format is widely used at NTU, however, this will not always playback on all computer and software combinations.
If your audio file is in a WMA file format or another typical file format (e.g. .m4a, .wav, or .amr) converting the file is highly recommended, try using the following resource or finding out more information from JISC Digital Media
on how to convert.
If conversion of the audio files proves to be difficult then consider uploading to an audio sharing website and then using the Insert video from a sharing website method for your delivery.
Audio file size
Audio file size, generally speaking, is not that critical. However, it is worth developing good practice to ensure that files are made available in an optimised version as possible. This will help usability in general, for example, on mobile devices where network speeds differ and more generally, where students are accessing materials on poorer internet connections. To find out how to optimise an audio file see the 'How to make an MP3' section of the User guide to MP3
by JISC Digital Media (it is recommended not to go into too much detail with the rest of the resource/s on this website).
Volume level
If you're experiencing problems with volume levels in your audio or between a batch of audio files, i.e. you'd like them to be consistent and one not louder than another, then there are a number of methods that can be useful, see Audio Post Production - Techniques for Spoken Word
by JISC Digital Media, and read down to and including 'Problems with volume'.
Splitting up your audio file into smaller pieces
It is often useful to split an audio file into smaller pieces when delivering online. This can help with signposting of the content and ease of navigation to a particular topic or part. Additionally, it will help with downloading times. To split up an audio file into several different pieces see Basic audio editing
by JISC Digital Media.
A useful tip is to instruct students using a slower connection to start downloading a subsequent piece of audio while listening to one that they already have downloaded.
Cleaning up your recording
It usually can be worthwhile to do some very basic editing to your recording. The most common actions you might want to consider doing are:
- Top and tailing - i.e. cutting any silence or noise at the beginning or end of a recording
- Removing a mistake or long silence during a recording
- Make a recording louder
- Make a recording a little clearer
To find out how to make the changes listed above see Audio Post Production - Techniques for Spoken Word
by JISC Digital Media, and read down to and including 'Removing background noise'.
Converting your audio file
There are a number of ways to convert an audio file into a supported file format. We recommend first trying this service http://media.io/
. Meida.io is an online audio converter which is very intuitive to use.
Another method for converting audio is to open a file in Audacity
and then exporting it as an MP3. Also see the 'How to make an MP3' section of the User guide to MP3
by JISC Digital Media (it is recommended not to go into too much detail with the rest of the resource/s on this website).
If Audacity does not support the file type that you are trying to convert than you will need to find and install an appropriate software converter that does support your file type (contact Information Services
and ask for an install or temporary administration rights to your computer so that you may install software yourself). A few free converters are listed below:
- Free Audio Converter
- Windows Expression 4
- Switch Audio file converter for Mac
or http://switch-mac.en.softonic.com/mac
If this process becomes difficult then contact the ITS Service Desk
(NTU login required).