A 500Hz tone alternates with a stepwise increasing comparison tone near 1000Hz. Which step seems to represent a correct octave?
Experiments on octave matching usually indicate a preference for ratios that are greater than 2.0. This preference for stretched octaves is not well understood. It is only partly related to our experience with hearing stretch-tuned pianos. More likely, it is related to the phenomenon we encountered in Demonstration 14, although in this demonstration the tones are presented alternately rather than simultaneously.
In this demonstration, a 500-Hz tone of one second duration alternates with another tone that varies from 985 to 1035 Hz in steps of 5 Hz. Which one sounds like a correct octave? Most listeners will probably select a tone somewhere around 1010 Hz.