Making windows media files smaller???
Are you asking about WMA (Windows Media Audio) formatted files, or audio files in general? If the following doesn't answer your question, or if you'd like some advice, please tell us a little more about what you're doing.
File size can be calculated from the
bitrate. With lossy compression formats, you can choose the bitrate, and if you know the bitrate, you can estimate file size (for any format) with the following formula:
File Size in MB = (Bitrate in kbps x Playing Time in minutes) / 140
With WMA files,
saving with Save As and choosing a lower bitrate will give you a smaller file (and lower quality).
GoldWave can open a file and then save it in a different format, but if you're not editing the audio, you don't really need an audio editor and you can use a more straightforward audio conversion program.
There are three categories of audio format:
1. Uncompressed (i.e. WAV). The size/bitrate is determined by the sample rate (kHz), bit depth (i.e. 16 bits), and number of channels (i.e. 2 for stereo).
2. Lossless compression (i.e. FLAC and lossless WMA). The file can be compressed to about 60% of the uncompressed file size. Of course, with lossless compression there are no quality issues. The audio quality is identical to the uncompressed file.
3. Lossy compression (i.e. MP3, WMA). Data is thrown-away, and you can compress to 1/5th or less of the uncompressed file size. Of course, here there
is a trade-off between file size and quality. Even though data is being thrown away, a high-bitrate MP3 will generally
sound identical to the original and will be indistinguishable in a blind "ABX test".