Patent ID: 6999590
Filing Date: 2006-02-14
Classification: H04S

Abstract:
1. A stereo sound circuit device for providing three-dimensional surrounding sound effect, comprising: a subtractor for concurrently receiving a left channel sound and a right channel sound, thereby performing a subtraction operation to acquire a difference signal of the left channel sound and the right channel sound; a difference amplifier connected in series to the subtractor for amplifying the difference signal; a filter circuit having first and a second filtering operation units for applying first and second filtering functions to the difference signal output from the difference amplifier for generating a three-dimensional surrounding sound signal, wherein the first filtering function implements a band pass filter with a central frequency of 7.23 KHz, and the second filtering function implements a band pass filter with a central frequency of 318 Hz; a signal level adjust circuit for adjusting the signal level of the sound signal output from the filter circuit; and a mixer for combining the adjusted three-dimensional surrounding sound with the original left channel sound and right channel sound.