Re-converting at same kbps rate - does that mean noticeable quality loss?

[DudeBoyz]

My bud has some 192k audio files that he used one of those free-ware MP3 Trimmer type of programs on to get rid of stuff at the front and end of the song to make 'em more seemless or whatever.

Now, some of his MP3 players don't show the right time and/or fast forward and rewind properly with those files.

He did a test and used PowerAMP converter to re-convert a file from 192k with the clips to 192k to help clean up the MP3 data table, and now it plays back just fine.

He was wondering if he has a 192k file converted originally with LAME and converts that file again to 192k with LAME if he will lose much quality.

I told him I didn't think much quality would be lost, since the key method of compressing audio is to eliminate the excessively high and excessively low frequencies, and it turns out the file size is within a few bytes of each other. But I'm no expert and wanted to ask folks here what the actual truth of the matter is.

If someone could help clarify, I'd appreciate it.

Thanks

[LtData]

Re: Re-converting at same kbps rate - does that mean noticeable quality loss?

There is a small quality loss, yes, but not very much, IIRC.

[DudeBoyz]

Re: Re-converting at same kbps rate - does that mean noticeable quality loss?

Thanks for the answer.

[Agharta]

Re: Re-converting at same kbps rate - does that mean noticeable quality loss?

Thanks for the answer.

Converting Lossy to Lossy does reduce quality.

It sounds like the MP3 header has been removed or damage. So a better option would be to use a utility that can rebuild the header of the MP3 file. This will avoid any quality loss, and save you time, because fixing the header is faster than re-encoding.

[DudeBoyz]

Re: Re-converting at same kbps rate - does that mean noticeable quality loss?

Converting Lossy to Lossy does reduce quality.

It sounds like the MP3 header has been removed or damage. So a better option would be to use a utility that can rebuild the header of the MP3 file. This will avoid any quality loss, and save you time, because fixing the header is faster than re-encoding.

I'm curious on a personal level about what the level of quality loss will be.

Unlike JPEG with pics, MP3's primarily (perhaps only) touch on a certain range of frequencies for their operation. The frequencies affected at 192k should be the same each time it is converted, right? So converting the same MP3 a second time with the same encoder should not change the core frequencies that were not changed in the first pass, correct?

Thanks