Superposition - Another Special Case:
Two pure tones with "simple" frequency ratio
like 2:1 or 3:2
Simple frequency ratios = HARMONY
e.g. 2:1 ratio = octave; 3:2 ratio = fifth.
resulting tone is periodic
find frequency of combined tone!
Example: 300Hz +200Hz (frequency ratio 3:2)
find largest common multiplier: 100 Hz - why?
after 1/100 sec, 300 Hz made 3 full oscillations
200 Hz made 2 full oscillations
thus waveform repeats exactly after 1/100 sec.
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