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????? ?????? ???? ????? ??? ?????????? ????? ?? ?? ?? ??? '?? ???? ?? ??? ????? ????? ??, ????? ?? ???, ???? ??? ??? ?????? ????? ??? ????? ?????? ?????? ?????? ???? ?????? ??? ????????? ????, ???? ??????? ?????? ?? ????? ??? ?????[1] ????? ????? ?? ????? ??? ????? 20 ????? ??? 20 ????????? ?? ?????? ???? ???? ?? ??? ????? ?????? ??? ???? ??? 20 kHz ??? ???? ?? ????? ?????????? ?? ??? 20 Hz ??? ??? ??????????? ??? ??? ??????? ???? ????? ??????? ?????? ???
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[????]- ↑ Fundamentals of Telephone Communication Systems. Western Electrical Company. 1969. p. 2.1.
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| Library resources about Sound |
- Sounds Amazing; a KS3/4 learning resource for sound and waves Archived 2025-08-07 at the Wayback Machine.
- HyperPhysics: Sound and Hearing
- Introduction to the Physics of Sound
- Hearing curves and on-line hearing test
- Audio for the 21st Century Archived 2025-08-07 at the Wayback Machine.
- Conversion of sound units and levels
- Sound calculations
- Audio Check: a free collection of audio tests and test tones playable on-line
- More Sounds Amazing; a sixth-form learning resource about sound waves Archived 2025-08-07 at the Wayback Machine.
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- Articles with FAST identifiers
- Pages with authority control identifiers needing attention
- Articles with BNE identifiers
- Articles with BNF identifiers
- Articles with BNFdata identifiers
- Articles with GND identifiers
- Articles with J9U identifiers
- Articles with NDL identifiers
- Articles with NKC identifiers
- Articles with EMU identifiers
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