Saturday, October 1, 9:00 am — 10:30 am (Rm 403A)
Jason Corey, University of Michigan - Ann Arbor, MI, USA
P18-1 Hyper-Compression, Environmental Noise and Preferences for the Ear Bud Listening Experience—Robert W. Taylor, University of Newcastle - Callaghan, NSW, Australia; Luis Miranda, University of Sydney - Sydney, NSW, Australia
The notion that compressed music performs more effectively in automobiles as a consequence of the background noise present has been widely accepted and particularly relevant to classical music with a very large dynamic range. The environmental noise can act as a masking agent that can interrupt the listening experience when sections of the music fall below the noise level. Similarly, it is assumed that the hyper-compression of contemporary popular music fulfills a similar function when using ear bud headphones in noisy environments. This study examines this assumption and can find no evidence to support the practice. It is suggested that contemporary music most likely does not have a sufficiently large enough dynamic range regardless to support its use in this instance.
Convention Paper 9657 (Purchase now)
P18-2 Validation of a Virtual In-Ear Headphone Listening Test Method—Todd Welti, Harman International Inc. - Northridge, CA, USA; Sean Olive, Harman International - Northridge, CA, USA; Omid Khonsaripour, Harman International - Northridge, CA, USA
Controlled, comparative double blind listening tests on different in-ear (IE) headphones are logistically impractical. One solution is to present listeners virtualized versions of the headphones through a high quality IE replicator headphone equalized to match their measured frequency responses. To test the accuracy of method, ten trained listeners evaluated the overall quality of both actual and virtualized versions of twelve different IE headphones binaurally recorded and reproduced through replicator headphone. The results show evidence that the virtualized headphones produce sound quality ratings that are similar to those produced by the actual headphones.
Convention Paper 9658 (Purchase now)
P18-3 The Physics of Auditory Proximity and its Effects on Intelligibility and Recall—David Griesinger, David Griesinger Acoustics - Cambridge, MA, USA
Cutthroat evolution has given us seemingly magical abilities to hear speech in complex environments. We can tell instantly, independent of timbre or loudness, if a sound is close to us, and in a crowded room we can switch attention at will between at least three different simultaneous conversations. And we involuntarily switch attention if our name is spoken. These feats are only possible if, without conscious attention, each voice has been separated into an independent neural stream. We believe the separation process relies on the phase relationships between the harmonics above 1000 Hz that encode speech information, and the neurology of the inner ear that has evolved to detect them. When phase is undisturbed, once in each fundamental period harmonic phases align to create massive peaks in the sound pressure at the fundamental frequency. Pitch-sensitive filters can detect and separate these peaks from each other and from noise with amazing acuity. But reflections and sound systems randomize phases, with serious effects on attention, source separation, and intelligibility. This talk will detail the many ways ears and speech have co-evolved, and recent work on the importance of phase in acoustics and sound design.
Convention Paper 9659 (Purchase now)