The Yamaha R-N803D is an integrated amplifier (for passive speakers), which means that it already has a power amplifier - just like the Beolab 9 speakers (which is why they are called active speakers). The combination of Yamaha R-N803D and Beolab 9 speakers therefore makes no sense. The Beolab 9 speakers need a so-called preamplifier, such as the Yamaha WXC-50 (
Yamaha WXC-50 (Preamplifier, Dark Silver) ), which I also use and can fully recommend.