However, CDs weren't popular in the early 80s.
Which explains itself pretty well if you look at the price of a CD player during that time. As always, it took the labels some catching up to do with technology, plus you needed a while for the tachnology to take hold before you could really start to mass-produce stuff. That was the case somewhen during the mid-90, when CD players actually became affordable, not just available.
Also, say if I'm wrong, but for some reason, I think that listening to a CD has better sound quality than mp3s.
MP3 is destructive data compression (i.e. you will not be able to restore the original data from an MP3), so the quality is by definition worse than the original, which usually is a CD. Wheather the difference is audible to a mortal man or not very much depends on how much you compress them, though.
If your original is better than CD quality, however, (say, 24 bit/96 kHz to take a common recording resolution, although professional equipment nowadays can again record much higher than that), it is not difficult to make an MP3 that has better quality than the .wav (.wav is nothing else than sound's .BMP: All the data is stored without any optimisation or compression whatsoever) that would go on the CD, while still taking up less space.
Feel free to correct me. But, there is also a limit on how high the quality of mp3s can be.
That's
encoded bits per second, not original bits per second. A CD has 706.5 kbps unencoded, which is not that much more if you consider how much of that data you can't actually hear.
Sure, a bat would protest most heavily at the loss of quality, but thankfully our ears are rather limited...
I believe that the SACD is 192 kbps sampling rate.
kbps is not sampling rate, it's the product of sampling rate times bit-depth, and 192 would be rather abysmal. As far as I can see it has 2822.4 kbps. The reason it never caught on is that it needed new equipment, which was more expensive and would have had to find a broader customer base to become affordable. The reason it didn't find a broader customer base is because the storage medium is only the first link in the audio quality chain. After that comes the Amp and the speakers. And to make that audio quality actually audible, you need really good speakers, and those cost a lot more money still. I.E. people would have to invest in very expensive speakers, a good amplifier and an expensive player to get a quality advantage most of them aren't able to hear.
The SACD did find some fans among connaisseurs of orchestral music, because they usually already have the expensive speakers and amplifiers, but beyond that there was just no demand for a little more quality at a high price.
Besides, I don't like to paying mp3s on iTunes, they are so compressed that it sounds lower than the actual CD.
Yes. That's the evil left from the olden days, where one gigabyte was the pinnacle of portable memory storage, and people were totally freaked out by the possibility of putting 20 albums in that space instead of one, and screw the quality, because those cheap headphones on my player sound crappy anyways. We must not forget that MP3 started its career as a portable format, and there's rarely people that have earphones on their MP3 players that cost in excess of 50 bucks. Which means, most of the time, they are crap anyways. So if you encode MP3s in a decent quality nowadays, you get people complaingin that it's too big and they might as well put the CD directly on their player or why it takes so long to download. It's getting better with our abbundance of storage space and bandwith, but I guess it'll still be some time until we get decently encoded MP3s in the stores. More bandwith in this case also means lower profit margins, after all, and labels still would rather sell CDs than MP3s.
