The
frequency response of the
human ear is generally agreed to be from 20 hertz (Hz) to 20,000 hertz. The
lowest sounds in
music are called
bass notes, and sound below 80 -100 Hz is considered deep bass. Hertz is the
term for how
fast something cycles or
vibrates per
second. If you had something turning or going
back and forth 20 times a second, (or 1,200 times a minute,) that thing would have a
frequency of 20 hertz. The higher the frequency (the faster the
motion), the higher in pitch the sound will be, and the lower the frequency (The slower the motion), the lower the
pitch.
If you have ever had engine noise leaking into your car stereo sound, you will remember that the noise rose and fell in pitch with the engine, letting you “hear” the engine’s speed. In a standard speaker with multiple cones, an electronic device called a crossover splits the music signal and sends the proper frequencies to each cone.