Thank you very much to all of you for your answers.
I also believe that keeping the music in files is safer than keeping it in streams on CDs, which are prone to scratches and to reading errors. (I also noticed that many of the pc recorded audio CDs give me errors when I try to rip them now, after 20 years from recording, although they are not scratched.) I have chosen the uncompressed wave format as I have enough space nowadays with these low prices per GB of the HDD. I will build a 4TB RAID1 in my HTPC to store the audio/video collection.
I have also been an amateur musician. I played drums in a band for an year or so, back in the day when I was a student. I was also very passionate about electronics and music. (I graduated the Electronics highschool and then in 2000 the Electronics and Telecommunication faculty, specialising in Engineering Physics). Nowadays, all of these are just history. (I even formally reeducated myself in Economics, specializing in Management a few years ago.) Still, I have some nice memories that I would rather not let go. Maybe the music from the CD collection is important to me more in this respect.
My tastes in music changed somehow, too. Nowadays I would rather listen to classical music, and rather at the Opera or Athenaeum. (They are very cheap here were I live now.) Still, I sometimes find myself with a desire to listen to my old favorite pop/rock music collection. I also play them on YouTube when I am lazy, but what about when I want quality, or when I run, or travel, or drive?! While I still have the CDs I was thinking why not ripping them, just to have the music for any further need, when the CDs will not be around anymore. So will I do now