How is the paper cone in a speaker able to reproduce any sound, and with such clarity?

Question

How is the paper cone in a speaker able to reproduce any sound, and with such clarity?

Answer 1

The paper cone is often terminated at its center with a permanent magnet and that is centered within an electromagnetic coil of wire.  The magnetism of the coil of wire varies in strength with the strength of an electrical signal analogous with the vibrations of sound being reproduced.  The size of the paper cone is highly efficient in reproducing sound vibrations with wavelengths bearing a relationship with cone dimensions.  Therefore small (tweeter) and large (woofer) speakers are often needed to accurately reproduce the entire range of sound from very high to very low frequencies.  Good speakers often come within carefully designed enclosures (speaker boxes) to enhance resonance and sound quality.  Analog (vinyl) records can often contain vibrations at frequencies above the human threshold of hearing but they interact with lower frequencies (as in a live orchestra) producing realistic sound (that digital recordings may pass up).  Outstanding guitar players often prefer analog vacuum tube amplifiers (rather than semiconductor or digital amplifiers) for sound quality (and to control desirable distortions from overdrive, etc.!).

Answer 2

A paper cone cannot reproduce any sound exactly, but it can get pretty close. Sound is merely our detection of tiny atmospheric pressure differences within sound waves between 20 and 20,000 hz (nominally). The conical speaker produces these pressure differences by moving air back and forth along the axis of propagation. That is not the only way that sound is produced, but as it turns out is a very good simulation for most sounds.

Sound is not the only way we sense pressure differences, there is also vibration below 20 hz which is felt in other parts of the body. Conical speakers cannot reproduce these very well at all (you need to use oscillating fan blades). For sounds above 15KHz you are better off using oscillating crystals.