Hey,

So we all know converting lossy-to-lossy is a bad idea. But, I had a buddy of mine burn me some music onto a data disc, and all the tracks are in Ogg Vorbis format--I have foobar2000, so I can listen to these files with no problem; however, I'm all about my iPod/iTunes and would like to convert the tracks and have them on my iPod.

Is there a way to convert the Vorbis files to AAC with a minimal-to-unnoticeable loss in audio quality? Perhaps by converting the Vorbis files to an intermediate lossless format, and then encoding them as AAC? (I'm an amateur, so if that's a really stupid idea and won't help, then I apologize for saying it.)

I have noticed that these Vorbis files have a "real-time" varying bit rate that seems to vary based on what is going on dynamically in the song at a given time, so I'm thinking that might pose a conversion quality problem as well.

Any help/advice would be appreciated. Thanks!

Transcoding the Vorbis files to a lossless format and then back to another lossy format gains you nothing. All you're doing is interposing a needless step of nothingness. Regarding the variable bitrate aspect, it bears no relevance as it's part of the standard.

If you fancy trying MP3 instead of AAC for wider hardware compatibility...

Just load the files up into Foobar2000, use "Edit/ Select All" to highlight them then right-click on the files and select "Convert/ Convert to...". Select "LAME (MP3)" in the Encoding Preset box then left-click on "..." to set the quality level. Anywhere between -V0 and -V3 will probably suffice. Hit "OK". Hit "OK" again on the Converter Setup tab then agree to the Transcode warning.

Job done!

Cheers, Slipstreem.

Actually, the software has to do this anyway... with most programs you won't see the decoded WAV file, but it needs to decode the data before it can re-code it.

The idea would be to use a high bitrate for the 2nd encode (you can't do anything about the 1st encode). There is data-loss every time you encode, and a high bitrate will minimize the additional data loss with the 2nd encode. ...If you are lucky the combined data loss will not result in any audio-quality loss.

All format conversions (transcoding, aka lossy -> lossy) involve converting to a "lossless" intermediate (usually wave since almost every codec can read and write it). You can't encode something without decoding it first, right?

Yes, don't use AAC: use Apple Lossless (which (most) iPods support). Of course, that will take up rather more room on the iPod than is usually desirable. But if that's not a concern -- for example, if you're only keeping them on there till you've listened to them -- then that would achieve what you ask.