Comparative Perceptual Assessment of Sound Quality: Cone versus Distributed Mode Loudspeakers

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Authors

  • Piotr Kleczkowski AGH University of Krakow, Poland
  • Paweł Małecki AGH University of Krakow, Poland
  • Dorota Młynaczyk AGH University of Krakow, Poland

Abstract

A conventional cone loudspeaker has a limited capacity for creating the impression of spatiality, while a distributed mode loudspeaker (DML) has an inherent ability to evoke it. DMLs have their specific drawbacks, but some of these can be compensated for. A key question arises – is it a cone loudspeaker or a compensated DML that is preferred by listeners? A listening experiment with carefully controlled conditions was carried out to answer this question; 30 subjects participated. The participants evaluated three stereo systems: one based on a DML speaker (with its power response equalized) and two conventional two-way active systems. Two perceptual attributes were evaluated: overall preference and spatial impression. A graded pairwise comparison was used as an experimental paradigm; the results were analyzed according to the law of comparative judgment. The findings indicated that, even though the DMLs achieved slightly lower ratings than the conventional systems on average, the perceptual differences were very small. This was confirmed by the hypothesis testing that was performed on the raw results of the pairwise comparisons.

Keywords:

distributed mode loudspeakers, loudspeaker evaluation, spatial sound, pairwise comparison, listening experiment

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