Choosing Your Encoding Settings

Authoring streaming media requires choosing certain encoding settings. The settings decisions you make are based on limitations of, among other things, the current state of software engineering, computer processing and the subjective nature of human hearing. Thankfully, how you make these encoding settings decisions is generally similar across all formats.

NOTE

Don't encode files that are already encoded. An encoded file sounds better if you begin with uncompressed source audio.

Any audio file that can be opened in a waveform editor can be saved (converted) as a Windows Media file.

Whether your source audio is spoken word, sound effects, or music, you must choose the bit rate, codec, and channel (mono or stereo) settings that are appropriate to your own and to your projected audience's needs prior to encoding. It's all about file size versus audio quality. Obviously you want your streaming audio file to sound as good as the available technology and bandwidth will allow. But you must also take steps to ensure that the stream reaches the user intact. Not everyone has broadband connectivity, so it's recommended that you choose the lowest bit rate setting you can get away with that still sounds acceptable. For instance: If you're authoring content that contains only a human voice (mono) speaking under normal conversational conditions, it isn't necessary to encode the streaming file at anything over 56Kbps (28Kbps is also recognizable). The voice will be heard and understood at 28- or 56Kbps, and you won't consume unnecessary bandwidth. If you're authoring encoded music files in stereo, however, listeners will have a more enjoyable sonic experience if you offer the streaming file at a higher bit rate (56Kbps minimum and above).

In these tutorials you'll use a 32Kbps (mono) encode setting for 56Kbps users and a 128Kbps (stereo) encode setting for DSL (or any other broadband format) users. It's possible to encode at higher bit rates but the sound quality isn't all that much better and, by keeping the high quality setting at 128Kbps, broadband users have headroom to use their connection for other tasks.

The encoder invisibly selects a codec based on your encoding settings. Advanced users can and may want to choose a specific codec.