With dbpoweramp ripper and converter I created the following 4 files from the same CD track:
1. ripped from CD to flac
2. ripped from CD to wav
3. converted #1 to wav
4. converted #2 to flac
Then I used WinMerge to compare 1 and 4 (flacs), then to compare 2 and 3 (wavs,) byte by byte. A simple compare tool like DOS FC is not suitable because if there is one character off, it can never resync as WinMerge does.
First the flacs. The comparison of these is less important than the wavs because we don't listen to flacs, they are just a storage bin, and also have metadata tags and padding that wavs don't. The flacs (1 and 4) are identical except for slight differences in the tags, and the length of "00" padding before the music data starts. The padding is all zeros. Also at the very end of file, the file that was converted from wav to flac manually has 15 additional bytes added to the end compared to the file that was converted from wav to flac automatically in the ripper. All rippers extract the wav data first then convert it to compressed format, they do these two steps automatically. I just did them separately and compared them to the automatic compressed version. The tag sections containing English track descriptions are slightly different but the audio data is identical inside the flac.
Now the wavs. This one is more important because the wavs are what we listen to whether it is the original wav file streamed from the HD, or the wav that results after decoding a flac. Both files are identical except for the first and last lines, which contain some english text and padding, so they are not music data, maybe the CD-TEXT data? The first line differs only in that one file has a tilde and the other has an apostrophe following the English word RIFF (audio file type designation.) Between the first and last lines is 36.1MB of data, perfectly identical. This is comparing wav data from the original CD to wav data after being converted to and from FLAC. dbpoweramp or flac has changed the first and last lines. I saw the difference in the first line, but I couldn't find any difference in the 5500 character long last line. It could be as small as the first line, only one character. There are 523679 lines of data in this 3 minute pop song.
The comparison report, generated in html, crashed my Chrome with 72.2MB of data displayed all at once!
