Whats the CSR control?
The CSR (Center-Side Ratio) control sets the relative levels of the center and side (i.e., left and right) channels when using LCR panning. When it’s turned all the way to the left, no signal is fed to the mono (center) bus and the PAN control works as normal. When it’s turned all the way to the right, with the PAN control set at center, the signal is fed to only the mono (center) bus. As you turn the PAN control from the center to the left, the signal is panned from the mono (center) bus to the left bus. And as you turn the PAN control from the center to the right, the signal is panned from the mono (center) bus to the right bus. With the CSR control set midway, and the PAN control at center, an equal amount of signal is fed to the mono (center), left, and right buses.