A Comparison Between Bass Management Parameter Selection Techniques for Multichannel and Multi-position Room Equalization

Traditionally, room acoustic equalization is performed to improve sound quality. In a multi-channel audio system, employing simultaneous multi-position room equalization, the selection of the bass management parameter(s) between the subwoofer and a satellite is important for accurate reproduction of sound at the listening positions. Presently, many systems, such as home-theater receivers, have selectable crossover frequencies with fixed decay rates. Furthermore, the crossover frequency is selected by the user through informal listening tests. However, a choice of a single bass management parameter (viz., the crossover frequency) can limit equalization performance in the crossover region at all listening positions as shown in this paper. Such limitations arise from interactions, due to complex addition (i.e., phase and amplitude) of the subwoofer and satellite response, and manifest as large spectral deviations in the crossover region. In this paper, we present a comparison in the equalization performance resulting from the automatic optimization of a single bass management parameter (viz., the crossover frequency) with an all-parameter optimization (viz., the crossover frequency and the decay rates) using the spectral deviation measure. As expected, the results indicate that the all-parameter optimization provides a significant improvement over the standard single parameter optimization

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