I have a significant number of LAME MP3 files done with 3.90.2 and higher aps and I'm wondering about the best method (or at least a recommended one) for changing them over to AAC format. I don't have a recording engineers ears anymore (as if I ever did) so I don't want this to become the quality vs filesize debate from Hell.

I'm getting a 15GB iPod (generation 3) and I'd like to put as much of this stuff on it as I possibly can. I've done my own testing using the newest version of Nero and it's updated AAC encoder (Nero version 5.5.10.35) and I can't hear a difference between AAC encoded files at 128Kbps with the Nero encoder and -aps stuff with LAME 3.93. Once again, it's all about how it sounds to me, not anyone else, right?

So I'm wondering about how to accomplish my task:

1) Do straight transcoding using the Nero encoder from LAME MP3 >>> AAC format...

or

2) Do a LAME MP3 >>> WAV conversion first and then do a WAV >>> AAC format.

I did a search on this board for any information similar to what I'm trying to do (and I know I'm not alone in this activity because of the new iPod's AAC support) so I hope to get some recommendations about this procedure as well as maybe some actually testing information about the downside of transcoding direct MP3 >>> AAC.

Thanks in advance for any assistance,
br0adband

Well, be prepared to take some heat about transcoding and stuff. Anyway...

Converting from MP3 directly to AAC using Nero is OK, Nero uses the FhG decoder.

But can you tell the difference between an AAC 128 and an AAC 128 transcode from APS? Saying 128k is OK is moot if the transcodes come out awful . . .

I should have been more clear in that statement, my apologies.

In my testing I ripped out some test tracks direct from a Tears For Fears CD and then encoded the resulting wav file with LAME 3.93 -aps and Nero 5.5.10.35 AAC. I also transcoded the LAME mp3 file I had just created to AAC with the Nero encoder. They all sound similar enough to these ragged old high frequency deficient ears.

That's all.

What's the best???

Nero
dbPoweramp
Easy CD/DA
Quicktime 6.3

Which is the best AAC encoder?

I did some limited testing and found transcoding mp3 to mp4 is not so great, you really can pick out the transcoded files, more in my opinion than transcoding mp3 to mp3...