Most everyday sounds are harmonic complex tones, not pure tones

Evidence

Complex tones can be regarded as the sum of several pure tones. If the frequencies of the pure tones are integer multiples of a common basic or fundamental frequency, the resulting complex tone is called an harmonic complex tone. Despite the fact that complex tones comprise several pure tones, complex tones occur much more frequently in daily life than pure tones. The vowels of human speech, for example, or the sounds produced by many musical instruments are harmonic complex tones. — Professor Dr.-Ing. Hugo Fastl, Professor Dr.-Ing. Eberhard, Psychoacoustics- Facts and Models, 701

Categorization

• DEFINE: Defines harmonic complex tone as integer multiples of a fundamental frequency.
• CANDY: A pleasant conversation nugget: the sounds we hear every day are built from integer multiples of a base frequency.