Hey Kim, the Tannoy TX2 system controller adds a bit of high shelf filter when run in Sub mode. So you can easily eliminate from your rig and use the XTi to provide some HF shelf eq. I recommend that you start with 2dB @ 2000Hz, and bring the frequency up to about 6300Hz until it sounds right to you. Also don't forget to kick in the 100Hz HPF on the XTi as well. Best, nappy.