Our brain has a remarkable ability to subconsciously reinterpret stimuli so that under certain conditions an acoustical signal impinging on the ear could differ from what our brain perceives. This discrepancy in sensation versus perception can be seen in various music compositions such as Brandenburg concerto for orchestra, where each section has disjointed movement but when put together the resulting orchestrations become a melodious piece. Pioneering psychologist Diana Deutsch has explored such auditory illusions through her research, including examples such as the octave, scale, chromatic and cambiata illusions. In this talk, we will describe an exploration of one of these auditory illusions - the scale illusion - performed with a binaural recording setup. Expansion of this experiment included using replications of the scale illusion played on two violins instead of synthetically generated sounds and using the binaural recording device to track sound in 3 dimensional space. The binaural recording method allows for alterations of the angle of incidence of the sound that could affect perception of the illusion as well as movement around the recording device to see if the scale illusion disappears and reappears or if the cone of confusion alters the illusion. Signal processing techniques including Fourier transformations and spectrograms were used to quantitatively analyze the frequency content of different data sets. The experimental measurements were performed in Phasor Lab in the Wold Science and Engineering Building.
It is suggested that attendees bring a smartphone and headphones so that they can listen to recordings related to the presentation.