hi im in need of help and you people are very intelligent individuals here. my question too you is I was given an 80gb 5.5 generation ipod from a friend and i have alot of mp2 encoded albums and the ipod cannot understand mpeg-1 layer2 so the files are mp2 320kbps 44100 and my question is would transcodein them too 256kbps aac ruin the files? if so would rockbox be a better alternative then taken hours of my time transcodeing them too apple aac if the end result would be worse ?
Iv'e never had to transcode anything and i know it's bad to do so if any kind person would read this and give me a straight answer to my problem it would be most appreciated thanks

Transcoding from lossy to lossy is bad, but if you don't hear the difference, and is only for portable use, I don't see why not. Bitrate of input file is rather high.

Well, I wouldn't transcode to a bitrate that is only one notch below 320kbps. If anything, I would transcode the files to a bitrate that is much lower than the source file. I am not sure what type of "mp2" files you have though as iPods can play mpeg-2 layer III audio (not to be confused with mpeg-1 layer III which is mp3) audio just fine.

As previously pointed out, there shouldn't be anything wrong with transcoding so long as you don't hear the audio flaws intorduced by a lossy-to-lossy process. We will be unable to give you a straight answer simply because everyone has different music, equipment, ears, and abilities to spot encoding flaws. I suggest that you transcode a couple of files, download a program called foobar2000 (install the ABX plug-in as well), and conduct a few blind ABX tests comparing the source files and the transcoded ones. Failing the test means that transcoding did not introduce any flaws that you were able to hear and that you can freely transcode without worrying.

@ B7K : Since you are starting with a high bitrate, and a codec that works in a different way than your target codec (mp2 to aac), the results are to be expected better than, say MP3 to MP3. Also, if you have to rockbox the iPod just for these files, maybe it's not worth the time.

The definitive judge is the one that has to hear them (in this case, you), so as suggested, give a couple of files a try and see if you hear anything wrong.

@kornchild2002 : MP2 is MPEG layer II. (either MPEG1 or MPEG2). MPEG2 layer III is still MP3, just with a lower sampling rate. Basically, MP2 is the codec used in standard DVD and DAB radio. ( Musepack has more in common with MP2 than with MP3 )
There existed also MP1, (layer I). Originally it was used on Digital Cassetes ( DCC's ).

Thanks for explaining Jaz. I wasn't sure what type of "mp2" files the OP had. I have seen that term being used to describe mpeg-2 layer III audio, I didn't know if the OP was doing the same thing as they wouldn't have to transcode if they had mpeg-2 layer III audio files. I also didn't realize that mp3 could be defined as mpeg-1 and/or mpeg-2 layer III audio. Learn something new everyday.

You shouldn't, since the file extension for MPEG-2 layer III is still .mp3. I'd imagine the only reason you can get away with that is that nearly all MP2 decoders also decode MP3, so a mislabeled MPEG2-Layer III file still ends up inside an MP3 decoder. The reverse isn't true though, since many mp3 decoders don't do MPEG1 layer II.

Yeah I Have decided on installing rockbox it plays all my mpeg1layer2 files from my old radio days and has made the ipod even better apples firmware blows thanks too all that helped me and keep up the good work you do here on these forums

The firmware on the 5g iPod and 1-2g Nanos was pretty good IMO, but the firmware on the iPod Classic sucks big time.

Ipod classic did suck Rockbox 3.2 on my 5.5th gen ipod is like taking my home stereo equipment and smashing and compressing it into a little thing you can handle in your pocket too cool

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