Editing Twelfth root of two (section)

==Pitch adjustment==
{{See also|Audio time stretching and pitch scaling}}
[[File:Monochord ET.png|thumb|One octave of 12-tet on a monochord (linear)]]
[[File:Pitch class space star.svg|thumb|The [[chromatic circle]] depicts equal distances between notes (logarithmic)]]

Since the frequency ratio of a semitone is close to 106% (<math display=inline>100\sqrt[12]{2} \approx 105.946</math>), increasing or decreasing the playback speed of a recording by 6% will shift the pitch up or down by about one semitone, or "half-step". Upscale [[reel-to-reel audio tape recording|reel-to-reel magnetic tape recorders]] typically have pitch adjustments of up to ±6%, generally used to match the playback or recording pitch to other music sources having slightly different tunings (or possibly recorded on equipment that was not running at quite the right speed). Modern recording studios utilize digital [[pitch shift]]ing to achieve similar results, ranging from [[cent (music)|cents]] up to several half-steps. Reel-to-reel adjustments also affect the tempo of the recorded sound, while digital shifting does not.