Thank you very much to everybody who posted and lead me on a way to understand my confusing ripping-problem. Sorry, it took so long for my answer, but I had to be away from home for a day unexpectedly.
Some checks I've made on the two .ape files:
- The files are on the same disk and in the same directory
- The file-sizes (right-click, properties) are different by 231'927 Bytes
- The compression level of both files is Monkey's Audio (APE)/normal. At least I think so, because I didn't change anything between the two rip procedures. In tag info I see Compression=Normal (3.99)
- The duration for both files is 13:43
- The bitrate is different 833 bps for the first file, 835 bps for the second
- BPM values are totally different 133/65 ?
- While listening to the two tracks, I don't notice any unexpected pops or hickups. But my ears are not this educated or especially sensitive. The CD is live-recorded and so there are many different sounds not only from the artists. BTW it's Dire Straits - Alchemy - Part Two, 03 - Telegraph Road.
As Alex and hit_ny suggested, i converted the .ape files to .wav. The result are two files with exactly the same size 145'177'244 Bytes.
Listener pointed to the technical value "read offset" of the two used dvd-drives. While I could find the value in the database for my external LG drive (+667), my internal drive NEC DV-5800A seems to old and is not mentioned. But, NEC drives seem to be in another range with their offset values.
Now, what can I do to get back my confidence in secure ripping on my PC.
A bit by bit comparison of the .wav files can be different due the read offset values despite identical sound information, if I understand everything right.
Every help is appreciated.
U.