I’ve been recording audio streams from my music player of choice using the X-Fi’s Audio Creation Mode’s recorder as it works well for my purposes. The streams come in @ 192, 160, & 128kps MP3 format depending on the internet station. I record the streams in WAV format (1411kps) so that I can later molest them (trim, mix, reverb, echo, etc.) in whatever way suits me @ the time and re-save them w/out losing much, if any, quality. I assumed that if I saved them in any lossy compression format I’d lose some quality after I worked on the files and resaved them. Make sense? Finally, I compress the finished (or untouched) files to AAC for personal listening.

My questions are (1) whether or not it makes any sense to do that final compression @ higher than 192kps AAC since that’s highest bitrate the source comes in as. When I used lossless encoding (for highest possible quality) the bitrate is never less than 1000kps which surprises me since the bitrate of the source is only 192kps at its highest. Even if I don’t toy with the WAV file and compress straight from the originally recorded file this remains the case.

I’ve settled on using between 224kbps and 320kbps for that final compression…(2) is this just a waste of space? (3) Would I get pretty much the same quality as the source, in your opinion, if I just compressed the files @ 192kps AAC? (4) Why do you think the lossless files remain at such a high bitrate when the source is so comparatively low? I had the expectation that the lossless files would be smaller because the WAV file is only capturing up to 192kbps audio. I apologize if I’ve not written this clearly (…went to public schools. 8O )

I know I may be delving in stupidity but I don’t have any audio engineering background and I obviously don’t have an understanding of how WAV and AAC compression really work.

Audio compression is highly subjective. In theory, the higher the bitrate is the more quality you should receive. Though, it doesn't make sense to encode a 192 kbps source file into something like a WAV file.

I'd go with the 224 ~ 320 kbps for final compression as you said. Since nearly all audio compression codecs that aren't lossless remove some audio quality, whether you notice it or not, you'll have that extra data in there to ensure it.

Put it this way.. If you took that 192 kbps source file, as if it existed on your hard drive, edited in WAV form, then saved as the same quality as the original it'll be compressing it even more. It's like saving a JPG picture over and over again in MSPaint or another program, every time you do it you lose a little quality. I highly doubt you'll lose an enormous amount by saving it 192 kbps, but you should try listening to the 192 kbps version and the higher bitrate versions. Whichever sounds better to you, use.


I bet an audiophile is going to come here and call me a retard for telling you to encode it at a lower bitrate.

Thanks for the reply. Unfortunately Creative's ACM doesn't allow recording in AAC (my format of choice since I use iTunes). I had to choose between WAV, WMA, and MP3. Like you noted, I know if I record in MP3 or WMA format and then edit and re-save the files I'll, theoretically, lose some audio quality...maybe not much, but I'd prefer to lose as little as possible when doing the re-save after editing. I don't want to waste disk space but the audio quality of the final files is kind of important to me.