When you store a voice segment in the database, you can save it in compressed format, uncompressed format, or both. Blueworx Voice Response uses a compression algorithm derived from the Groupe Speciale Mobile (GSM) digital mobile phone system, which gives high-quality voice suitable for telephony applications. Saving voice segments in a compressed format saves disk space and bus bandwidth (the compression ratio is 5:1), but tends to cause a slight loss of sound quality. If you compress a voice segment, then uncompress it, the sound quality of the resulting voice segment will not be equivalent to that of the original. However you can support more channels (more simultaneous calls) by using compressed voice.
If, on the other hand, it is important to preserve the highest possible sound quality, choose uncompressed format.
You can mix compressed and uncompressed voice segments in the same application using the System : PlayPrompt voice compression type system variable (SV182) to specify the compression type (or the System : Voice segment compression type system variable (SV50) if you are using the PlayVoiceSegment action). You might, for example, use uncompressed segments in the opening dialog and most frequently used menus, to give a good impression, but use compressed segments for less frequently used, or less essential, information.