Download Time and Frequency Domain Room Compensation applied to Wave Field Synthesis In sound rendering systems using loudspeakers, the listening room adds echoes not considered by the reproduction system, thus deteriorating the rendered audio signal. Specifically, Wave Field Synthesis is a 3D audio reproduction system, which allows synthesizing a realistic sound field in a wide area by using arrays of loudspeakers. This paper proposes a room compensation approach based on a multichannel inverse filter bank calculated to compensate the room effects at selected points within the listening area. Time domain and frequency domain algorithms are proposed to accurately compute the bank of inverse filters. A comparative study between these algorithms by means of laboratory experiments is presented.
Download Intermodulation Effects Analysis using Complex Bandpass Filterbanks The objective of this paper is to show the ability of complex bandpass filterbanks to extract the intermodulation information that appears when two audio signals interact inside the same analysis band. To perform the analysis a sinusoidal model of the signals has been assumed. Three kinds of signals have been analyzed: a sum of two cosines, a sum of two linear chirps and a sum of two exponential chirps. The complex bandpass filtering of the signals is carried out using a new algorithm based on the Complex Continuous Wavelet Transform. The developed algorithm has been validated comparing the practical results with the theoretical instantaneous amplitude and instantaneous phase of the obtained model of the signals. With the appropriate width, the complex bandpass filters show the same behaviour as our perceptual ability to discriminate interacting tones when they fall inside a critical band of the human ear.