Editing Harmonic series (music) (section)

== Timbre of musical instruments ==
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The relative [[amplitude]]s (strengths) of the various harmonics primarily determine the [[timbre]] of different instruments and sounds, though onset [[transient (acoustics)|transients]], [[formant]]s, [[noise]]s, and inharmonicities also play a role. For example, the [[clarinet]] and [[saxophone]] have similar [[mouthpiece (woodwind)|mouthpiece]]s and [[reed (music)|reeds]], and both produce sound through [[resonance]] of air inside a chamber whose mouthpiece end is considered closed. Because the clarinet's resonator is cylindrical, the ''even''-numbered harmonics are less present. The saxophone's resonator is conical, which allows the even-numbered harmonics to sound more strongly and thus produces a more complex tone. The [[inharmonicity|inharmonic]] ringing of the instrument's metal resonator is even more prominent in the sounds of brass instruments.

Human ears tend to group phase-coherent, harmonically-related frequency components into a single sensation. Rather than perceiving the individual partials–harmonic and inharmonic, of a musical tone, humans perceive them together as a tone color or timbre, and the overall [[pitch (music)|pitch]] is heard as the fundamental of the harmonic series being experienced. If a sound is heard that is made up of even just a few simultaneous sine tones, and if the intervals among those tones form part of a harmonic series, the brain tends to group this input into a sensation of the pitch of the fundamental of that series, [[Missing fundamental|even if the fundamental is not present]].

Variations in the frequency of harmonics can also affect the ''perceived'' fundamental pitch. These variations, most clearly documented in the piano and other stringed instruments but also apparent in [[brass instrument]]s, are caused by a combination of metal stiffness and the interaction of the vibrating air or string with the resonating body of the instrument.