Decoding a WAV results in the flash.media.Sound data format 44.1Khz,Stereo,32bit (float).
You can play it with the dynamic Sound API. Encoding can be done by simply passing the data you created in SAMPLE_DATA_EVENT to the encoder after specifying the target wav-format. You have to finalize the encoder after writing. Both processes are on the fly – processing block by block. They do not have to be processed in a single Flashplayer frame time.
Please check out IWavIOStrategy, if you want to implement new wav-formats.