The antenna supplied must be mounted on my window, otherwise nothing works. Our house is built earthquake-proof with a lot of iron. I bought a small special antenna that amplifies the signal with electricity and can be placed behind the unit without any problems.
I use the Yamaha Receiver R-N803D with 2 x speakers from Dali (Oberon 3). If you turn up the bass control on the Yamaha receiver, the bass comes across strongly. Nothing vibrates and the sound remains crystal clear.
This combination is absolutely brilliant for us.
I recommend connecting your Bose speakers directly to the Yamaha receiver. I am of the opinion that the speaker cables must be of high quality (I have the Oehlbach SP25 without any cable lugs). However, it could well be that passive speakers would work better.
Good luck with the trial and error.
If by modem you mean the router of the Internet provider, then of course that is possible; I have also connected my receiver via Erhernet. In terms of performance, the boxes and receiver fit together well.
I can't say anything about Windows. With the Mac, however, it works without problems. Regarding internet radio: Download the Musiccast app. Then it's easier to search for web radio and save your favourites. Or you can install Tunein on your computer, tablet or phone. Then you can select the Yamaha as the output source. It couldn't be easier.
The unit has only 2 output stages. These can be connected to the outputs A, B or A+B (parallel). Bi-amping is therefore not possible. The A+B circuit is more like bi-wiring.
Regarding the power of the speakers: It is important that the impedance does not fall below the minimum of 4 ohms (which the unit supports).