Question

similarity between high pitched sound and low pitch sounds

Answer 1

The terminology of "low" is vague and industry related. The old term for measurement was defined as cycles per second (CPS). The newer term is Hertz (Hz) to honor the researcher from the 1800's. It refers to movement of air which our ears then translate to sound. The air moves forward, backward and returns to it's starting point. That is one cycle. How many times it does that in one second determines how high or low the sound is. In most textbooks, the human ear is supposed to be able to hear from 20Hz to 20,000 Hz. A typical male baritone voice centers around 400Hz. The typical female voice is around 1,000Hz. The lowest note on a string bass is about 34Hz. Some massive pipe organs can go down 16Hz. What we hear is not just the main note (the fundamental or tonic), but higher, secondary vibrations (the first harmonic) which are about twice as high. So while 34Hz is being played, we will hear 64Hz also and then maybe 128Hz (the second harmonic) as well. In fact, we may hear 64Hz louder than 34Hz. These are referred to as harmonics or overtones. How many there are and how loud each of them are will tell you the tone (or timbre) so that you can tell which instrument is playing the note. I can go to my workbench and create a 10Hz note. You can't hear it, but if you put your hand on the speaker, you can feel it. An earthquake is an example of massive power moving everything including air. During an earthquake, you might hear the harmonics, but everything is moving, so it's hard to tell what you're hearing, but you might hear 20Hz. You can definitely feel it. If a sousaphone player comes up behind you and plays a scale, your body will respond more intensely to certain pitches, while you're hearing the higher harmonics or overtones. So good example of low pitch sounds are a bass drum, Tympani, a string bass, an electric bass, a synthesized sound like you could make in a recording studio or even some singers. I consider bass anything below the male, human voice - less than 400Hz. There are many ways to fool the ear into thinking that sounds are lower than they are and many speaker designers and recording engineers use these techniques. If you were to stand next the diesel engine in the engine room of an oil tanker, you would hear some seriously low notes there too.