What about CDs?

Let’s talk about CDs.

First you must remember that the specification for CDs was developed way back in 1979. At that time the cost of electronics was quite high compared to what it is today, particularly as it relates to their speed.

The CD specification just barely covers the audio spectrum that the human ear can hear, that is, 20 cycles to 20,000 cycles per second.  This represents the lowest and highest sounds that a typical ear can hear although many of us hear though a substantially narrower range, and a few of us can hear beyond this range.