So, all that we know as "sound" is merely vibrations moving through the air. We often represent this as a wave, because it has a measurable frequency, and amplitude.
All music is merely just vibrations in the air, it hits our ear drums, which sends a signal to the brain, and then we interpret that.
So we communicate to each other with this handy device built into our bodies over time through evolution, we call it vocal chords. It's a series of strings in our throat, we pass air over them as they're vibrating in certain ways.
Some 200,000 years ago when our species just started to surface, someone got the bright idea to use it as a musical instrument. Ever since, we've developed a lot of different sounds.
Now, you say Chris Cornell has a great range as a singer. He can sing high and low pitched. All that means is that he can sing with his vocal chords vibrating very fast or vibrating very slow. If they're vibrating fast, it's synonymous with singing "high," just two different ways to say the same thing.
That doesn't make him special. Lots of singers have a big range. They can make their vocal chords vibrate extremely fast and extremely slow. Why Chris Cornell is special is not how high and low he can go, but the timbre of his voice, which is just the shape of the wave. That's a totally unique thing to him and no other human has the same timbre as he does. Every voice is different and has a different timbre.