I have been using the B50 as a preamp for my sound bar. The TV can be connected to the B50 via the optical or USBC input in parallel to the HDMI. The B50 then connects to the Q990B via Bluetooth. Why? the DSP chip in the B50 has settings for EQ, harmonic excitation and stage depth which can be accessed through the ACP workbench tool. Different EQ/DSP settings can be saved to locations 0 to 5 which correspond to the 6 EQ presets on the IR remote / app.