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Physics · 术语表

什么是 Harmonics？

又称： fundamental · harmonic · pure tone

Definition 21.13 High School Physics · 第 21 章 — Sound and Acoustics

A periodic sound of frequency $f_1$ — the fundamental — is in general a sum of sines at the frequencies $f_n = n f_1$ , $n = 1, 2, 3, \dots$ , its harmonics. A sound reduced to its fundamental is a pure tone, like a tuning fork’s.

示例

Example 21.15 (Why you recognize the caller)

A flute’s A is nearly a pure tone; a violin bowing the same $220\,\mathrm{Hz}$ adds strong harmonics at $440\,\mathrm{Hz}\text{, }660\,\mathrm{Hz}\text{ and }880\,\mathrm{Hz}$ . Same pitch and loudness, yet no one confuses them: a voice, too, is a spectrum you know by heart.

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