Abstract: A sound signal processing device causes an amplifier to amplify a low frequency signal and synthesizes the amplified low frequency signal with a middle or high frequency signal so as to output the resultant output signal. A gain control section controls a gain of the amplifier on the basis of an amplitude of the output signal. As a result, it is possible to amplify the low frequency signal without any clipping in a receiving end device and without any unstable volume of a middle or high frequency component.

Abstract: In a filter coefficient calculation device according to the present invention, a gain correction characteristic calculation section calculates impulse responses corresponding to a linear-phase filter having an inverse characteristic of a gain characteristic of a reproduction system, and calculates, as a gain correction characteristic, a frequency characteristic of continuous-time impulse responses that include a peak value, the continuous-time impulse responses being impulse responses, clipped from the calculated impulse responses, whose number is identical to the preset number of filter taps.

Abstract: A sound signal processing apparatus (100) includes: an equalizer (110L) for enhancing an 8 kHz band of a sound signal (#1L); an equalizer (110R) for enhancing an 8 kHz band of a sound signal (#1R); and a filter (120) for delaying a phase of a sound signal (#2L). The filter (120) decreases correlation between the sound signals (#3L) and (#2R). This sufficiently moves a sound image upward, without use of a technique of pseudo surround.

Abstract: A sound signal processing device causes an amplifier to amplify a low frequency signal and synthesizes the amplified low frequency signal with a middle or high frequency signal so as to output the resultant output signal. A gain control section controls a gain of the amplifier on the basis of an amplitude of the output signal. As a result, it is possible to amplify the low frequency signal without any clipping in a receiving end device and without any unstable volume of a middle or high frequency component.

Abstract: In a filter coefficient calculation device according to the present invention, a gain correction characteristic calculation section calculates impulse responses corresponding to a linear-phase filter having an inverse characteristic of a gain characteristic of a reproduction system, and calculates, as a gain correction characteristic, a frequency characteristic of continuous-time impulse responses that include a peak value, the continuous-time impulse responses being impulse responses, clipped from the calculated impulse responses, whose number is identical to the preset number of filter taps.

Abstract: A process for producing a polymer of a diallylalkylammonium halide which comprises polymerizing the diallylalkylammonium halide in the presence of a polymerization initiator in an aqueous solution containing a nitroxy radical.

Abstract: A process for producing an aqueous dispersion of a water-soluble cationic polymer which process comprises modifying a polymer obtained by homopolymerization of an N-vinylcarboxylic acid amide or copolymerization of an N-vinylcarboxylic acid amide and a vinyl monomer copolymerizable with the N-vinyl carboxylic acid amide with an acid in an aqueous medium in the presence of a nitrate ion. The process can produce an aqueous dispersion of a water-soluble cationic polymer having a high molecular weight from the above water-insoluble polymer easily in a single step without causing adverse effects on the handling property while the fluidity is maintained.