Patent ID: 6108430
Filing Date: 2000-08-22
Classification: H04R,H04S

Abstract:
A headphone apparatus comprising:a signal processing circuit for performing signal processes to input audio signals of N channels where N is an integer of 2 or more;headphones to which an output signal of said signal processing circuit is supplied;detecting means for said headphones for detecting a rotation of a head of a user of said headphones; anda circuit for outputting control data based on a detection output of said detecting means,wherein said signal processing circuit includes:2N digital filters for convoluting impulse responses obtained by converting head transfer functions from N sound sources provided at positions for orienting said input audio signals to right and left ears of a listener into time regions to said input audio signals of said N channels,first and second forming means to which said outputs of 2M digital filters corresponding to M (M.ltoreq.N) channels as front channels among said N channels are inputted for forming outputs based on each of a component of a left channel and a component of a right channel,a first time difference adding circuit to which an output of said first forming means is inputted,a first level difference adding circuit to which an output of said first time difference adding circuit is inputted,a second time difference adding circuit to which an output of said second forming means is inputted,a second level difference adding circuit to which an output of said second time difference adding circuit is inputted,third and fourth forming means to which outputs of 2 (N-M) digital filters corresponding to remaining (N-M) channels among the digital filters of said N channels are inputted for forming outputs based on said output of said digital filter of said left channel and said output of said digital filter of said right channel,fifth forming means for forming an output signal based on said output signal of said third forming means and on said output signal of said first level difference adding circuit, andsixth forming means for forming an output signal based on the output signal of said fourth forming means and said output signal of said second level difference adding circuit, whereina first control is performed with said control data giving a time difference to said first and said second time difference adding circuits,a second control is performed with said control data which gives a level difference to said first and said second level difference adding circuits, andsaid output signals of said fifth and sixth forming means are supplied as said output signal of said signal processing circuit to said headphones.