It is also good networking practice to reserve IP addresses in router.
If not reserving the IP in router, the IP you give it has to be outside the range of IP addresses your DHCP server (in router) provides. Otherwise there could be a conflict and then two devices won't work or potentially the entire network stops depending on router.
If you insist on giving BDA-3 a dedicated IP address then you need to ensure your DHCP server does not give out that address.
So you could assign 192.168.1.100 - 192-168.1.200 to dhcp server (the 1 after 168 can be any number between 1-253)
Then assign one static address between 192.168.1.10 - 192.168.1.99 in the BDA-3.
Good place to start would be the name and model of your router and "how do I reserve IP address" in a google search. Much easier I think.
Bryston tries to make this easy by reserving the name http://my.bryston.com
to its ipaddress but this depends on how often the router updates the name to the IP address the BDA-3 has been provided. Which will also improve if you use the reserve IP address for the BDA-3.
I'll get my BDA-3 tomorrow so might add once I get hands on experience.
If your router is under warranty many companies would provide this support through email or phone.