1. WAV files
2. Real Audio
3. Midi
4. MP3

Wav files are currently the most popular audio file format. This is because it is the format defined and endorsed by Microsoft and used by Windows based computers. Today wav files are supported by most of the common platforms and by Netscape and the Internet Explorer.

Take care to avoid any breaches of copyright. Note that it is also fair that you copy the audio file on your server and do not link to a file on another server. Not only will this avoid the possibility that you sound suddenly disappears, it saves servers being overloaded.

Real Audio is audio compression and streaming technology that is frequently used on the internet. The technology is not in the public domain and as such you must download the plugin player and encoder from www.real.com.

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Wav files can have a range of sample rates and different sample types. Without going into the technical detail, PCM is the purest audio format, and offers much better sound quality than other compressed formats such as ADPCM or Real Audio (see below). The downside is that file sizes are large. A high sample rate provides better quality audio but has a much larger file size. Similarly, 16 bit PCM gives less hiss but has a file size double that of 8 bit PCM. As a general rule, you will not be able to viably embed an autostart file which is longer than 10 seconds. To have longer recordings you will need to use Real Audio (see below).

For a reasonable quality short voice prompt we recommend 11,025kHz, 8 bit PCM Wav Files.

To record and edit a wav file download a shareware editor:

Real Audio is audio compression and streaming technology that is frequently used on the internet. The technology is not in the public domain and as such you must download the plugin player and encoder from www.real.com.

Advantages:

Disadvantages:

Works only on some servers (It depends on the MIME configuration). If this does not work properly visit the Support Pages of www.real.com which describes how to set up the server MIME configuration and write ram files.

Midi files are much, much smaller than wav files and, if the user has a good sound card, the quality can be much better.

There are thousands of midi files available on the internet. Again, take care to avoid breaching any composer's copyrights.

Note that the sound of the music depends very much on the quality of the midi player. Listen to your selected music on a variety of sound cards before embedding the audio since some sounds that sound very good on good sound sources can sound awful on cheaper players.

MP3

Mp3, like Real Audio, is audio compression and streaming technology that is frequently used on the internet. To use mp3 you must have installed a player such as WinAMP or the Real Audio Plugin (from www.real.com).

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Disadvantages:

Works only on some servers (It depends on the MIME configuration). If this does not work properly, ask your server to setup the MIME type for mp3.

For better streaming (more immediate play) use a text editor to write a "m3u" file with a new line something like: http://www.yoursite.com/file.mp3.  Save the file as "file.m3u" and upload it to a Playlist.