Physical Changes in Sound
Pitch Change: Happens when the frequency of the sound wave changes. Higher frequency = higher pitch.
Volume Change: If the amplitude of the wave increases, the sound gets louder.
Doppler Effect: A sound seems higher-pitched when it’s approaching and lower when moving away (like an ambulance).
Echo & Reverb: In large or empty spaces, sound reflects and changes how it’s heard.
2. Environmental Effects on Sound
Temperature: Sound travels faster in warm air than in cold air.
Medium: Sound changes if it's moving through air, water, or solids. For example, sound is faster in water than in air.
Obstacles: Walls and objects can absorb or reflect sound, changing how it’s heard.
Distance: The farther you are, the quieter and more muffled the sound becomes.
3. Linguistic Sound Change (if you're asking about language)
Assimilation: One sound becomes more like a nearby sound. E.g., “handbag” becomes “hambag.”
Elision: A sound disappears. E.g., “family” sometimes sounds like “famly.”
Metathesis: Switching sounds around. E.g., “ask” becoming “aks.”
Vowel Shift: Major historical changes in vowel pronunciation (like the Great Vowel Shift in English).
4. Digital or Technical Changes
Auto-tune: Adjusts pitch to correct or modify vocals.
Equalization (EQ): Changes specific frequency ranges (bass, treble, mids).
Compression: Reduces dynamic range to make sound more even.
Filters/Effects: Echo, reverb, distortion — all modify the original sound.