Sound, Radio & InformationTelecommunications

Why Phone Calls Sound Muffled

Phone lines cut off the frequencies that tell ‘f’ from ‘s’

On a phone call, the “F” you spell out can arrive as an “S”. What is the line throwing away?

You'll find out

  • How much of your voice a phone keeps
  • Where an s and an f really differ
  • What changes with HD voice calls

Why it matters

Calls still squeeze a voice into a narrow slot; knowing what gets cut explains the mix-ups.

About 3 min6 interactive slides · 5 questionsLesson 246 · Zone 28

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