Patent ID: 6498856
Filing Date: 2002-12-24
Classification: H04R,H04S

Abstract:
A vehicle-carried sound reproduction apparatus, comprising:a correction filter circuit for converting input digital audio signals XL(Z) and XR(Z) for left and right channels into digital audio signals YL(Z) and YR(Z) represented, using head transfer functions, respectively by YL&af;(Z)&CenterDot;â€ƒ&it;GLL&af;(Z)+YR&af;(Z)&CenterDot;GLR&af;(Z)=XL&af;(Z)&CenterDot;FLL&af;(Z)+XR&af;(Z)&CenterDot;FLR&af;(Z)YR&af;(Z)&CenterDot;â€ƒ&it;GLL&af;(Z)+YL&af;(Z)&CenterDot;GLR&af;(Z)=XR&af;(Z)&CenterDot;FLL&af;(Z)+XL&af;(Z)&CenterDot;FLR&af;(Z)where, because the head transfer functions are leftwardly and rightwardly symmetrical with each other, the relationships of FLL(Z)=FRR(Z), FLR(Z)=FRL(Z), GLL(Z)=GRR(Z) and GLR(Z)=GRL(Z) are satisfied, and FLL(Z) is a head transfer function from a first speaker for the left channel positioned forwardly of a listener in a vehicle chamber to the left ear of the listener, FRR(Z) is a head transfer function from a first speaker for the right channel positioned forwardly of the listener to the right ear of the listener, FLR(Z) is a head transfer function from said first speaker for the left channel to the right ear of the listener, FRL(Z) is a head transfer function from said first speaker for the right channel to the left ear of the listener, GLL(Z) is a head transfer function from a second speaker for the left channel positioned at a lower position forwardly of the listener to the left ear of the listener, GRR(Z) is a head transfer function from a second speaker for the right channel positioned at a lower position forwardly of the listener to the right ear of the listener, GLR(Z) is a head transfer function from said second speaker for the left channel to the right ear of the listener, and GRL(Z) is a head transfer function from said second speaker for the right channel to the left ear of the listener; anda digital to analog converter circuit for converting the digital audio signals YL(Z) and YR(Z) outputted from said correction filter circuit into analog audio signals; the analog audio signals outputted from said digital to analog converter circuit being supplied to said second speakers for the left and right channels.