Phaseless upmixer system
View Patent ↗This sound processing system creates surround effects by minimizing quality degradation experienced by known sound processing systems in non-optimum listening environments such as vehicles. The sound processing system may include taking two channel input stereo signals and upmixing the input signals into at least two output signals where the phase of the output signals remains unchanged from the input signals. Once the output signals are generated by the upmixer, all pass filters can be adjusted based on the distance of the listeners from the loudspeakers to obtain the desired all pass filter frequencies and Q values.
1 . A vehicle sound optimization method, comprising:
inputting two or more audio channels to a phaseless upmixing module using a phaseless upmixing matrix;
outputting output signals of more than two audio channels, where the two or more audio channels are processed by the phaseless upmixing module without any modification of the phase of the two or more audio channels;
using the phaseless upmixing module to build a surround field L′, C′, and R′ using three sonic components that are center (C′), differential (L′, R′) and intermediate (L′−C′ and R′−C′); and
tuning the output signals of the more than two audio channels to optimize a sound field for a vehicle loudspeaker system to achieve an optimized phase alignment and consistent total energy in a vehicle having the vehicle loudspeaker system.
2 . The vehicle sound optimization method of claim 1 , further comprising allowing a user to input distances from a listener's position to the left and right loudspeaker by interfacing with a tuning panel where the input distances are used to provide optimization of the output signals to achieve phase equalization from the phaseless upmixing module.
3 . The vehicle sound optimization method of claim 1 , further comprising a setup mode that reduces complexity of setup and optimization of correction filters by allowing the user to input simple distances to define the correction filters.
4 . The vehicle sound optimization method of claim 1 , further comprising where the more than two output channels are phase coherent with differential and intermediate signals on a same side of an input spectrum.
5 . The vehicle sound optimization method of claim 1 , further comprising where there is no phase manipulation and acoustic phase is dependent upon loudspeaker placement and room reflections by using the phaseless upmixing matrix.
6 . The vehicle sound optimization method of claim 1 , further comprising where there are no steering angle computations by using the phaseless upmixing matrix.
7 . The vehicle sound optimization method of claim 1 , further comprising where there are no automatic level adjustments by using the phaseless upmixing matrix.