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Physics · 术语表

什么是 Pitch and loudness？

又称： pitch · loudness

Definition 21.5 High School Physics · 第 21 章 — Sound and Acoustics

Pitch is the perception of frequency: the higher $f$ , the higher the note; concert A is $440\,\mathrm{Hz}$ , and doubling $f$ raises the note one octave. Loudness is the perception of amplitude: the stronger the pressure oscillation, the louder; amplification changes loudness, not pitch.

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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