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Summary
DescriptionComma pump Benedetti first last.mid
English: First and last chords from Giovanni Benedetti's 1563 two measure example of a comma "pump" or drift by a syntonic comma (21.51 cents) during a progression. Common tones between chords are the same pitch, with the other notes tuned in pure intervals to the common tones. The progression is run four times, thus the notes of the chord are 86.03 cents apart.
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