Overtones and timbre

In short: An instrument never produces just a pure tone but a fundamental plus overtones. Their mixture determines the timbre by which we tell a piano from a flute even at the same pitch.

In more detail: Overtones are whole-number multiples of the fundamental frequency. With the note A at 440 Hz, 880 Hz, 1,320 Hz etc. also sound (schall-und-dezibel).

In detail

• Fundamental and harmonics: The first harmonic is the fundamental, the second an octave higher.
• Sine tone: A pure tone without overtones sounds cool and artificial.
• Attack and decay: How a tone begins and ends also shapes the sound (touch, envelope).
• Formants: In voices, resonance ranges of the mouth cavity determine vowels.
• Synthesizers: Generate sounds by mixing waveforms (sine, square, sawtooth).
• Tuning: Just intonation and equal temperament differ in intervals (stimmung-und-tonhoehe).