Method to Control Audio Volume and Pan Angle in a Stereo System by a Personal Computer
Original Publication Date: 1988-Apr-01
Included in the Prior Art Database: 2005-Feb-15
A method is described to provide user/PC control of Audio Volume and Pan Angle. This method assumes the presence of a Hardware Volume and Mix control (VMX) described in [*]. For this discussion, control of only half of the VMX will be described, since the VMX consists of two functionally identical halves whose outputs are simply summed (L + L and R + R). The simplified functional diagram is shown in Fig. 1. In Fig. 1 D1 and D2 are digitally-controlled attenuation units (separately addressable), A input is an Audio input signal and L and R are independent audio outputs. (Image Omitted) It is assumed that the VMX and VMX software is used in a system where the L and R outputs are connected to separate power amplifiers, which in turn are connected to audio speakers (or headphones) as shown in Fig. 2.