Assertion: piano keyboard's octave | /r/HasProperty | stretched
Facets:
Source sentences:
text: The inharmonicity of piano strings requires that octaves be stretched, or tuned to a lower octave's corresponding sharp overtone rather than to a theoretically correct octave.
text: When octaves are stretched, they are tuned, not to the lowest coincidental overtone (second partial) of the note below, but to a higher one (often the 4th partial).