Measuring Imaging - A New Tool for Tuning Audio Systems 2010-01-1152
Automotive audio systems require signal processing to address losses of spatial rendition of stereo and multichannel sources due to off-centerline listening and the proximity of cabin walls where the speakers are located. The digital signal processing is optimized for each vehicle type and audio option by skilled tuning engineers. They spend the majority of their tuning time on spatial issues when preparing a vehicle. One reason for this is that, until now, there has been no measurement of imaging performance. Engineers have relied on the indirect measures of arrival delay, spectrum and their own hearing to balance the several speakers likely to be contributing to perceived direction, distance and ambience. This paper describes a new module for a measurement system widely used in automotive audio. In addition to assisting the tuning engineer, the system documents audio performance in Tonal Balance, Maximum Output, Distortion, and now, Spatial Rendition.