It’s not possible to connect the Arc to your Novafidelity wirelessly - You would need a Sonos Port.

Page 97 of the X45 manual is titled “ The X45 works as a Music Server with Sonos “. There are no details, so you need to ask them HOW to do this. It has a Samba Sever so I am guessing that is how.

Thanks for the responses - would it work if connected via ethernet?

Also the x45 has network protocols like UPnP Server/Client/Renderer, Samba Server/Client... could these not be configured to connect to the Arc as a new Music Library?

Sorry, I was a bit quick to rule this out. 

You paid a ton of money for that hardware (a lot more than you paid Sonos I’ll wager), you should be asking the folks who got that money these questions IMHO. Their documentation seems very lacking in detail on these options.

Ethernet or wifi makes no difference, its just tcp/ip both ways.

You could be right there! Thing is, I got a good deal on the X45 and got it to finally RIP all my CDs and Vinyl then get rid of them…the Arc is used for TV and obvs if I can use it with the X45 then bonus. I’m not some kind of music purist that wants the ‘best’ possible sound but to have all my music collected over years RIPed and stored digitally and finally sell all my records.

You can probably tell I don’t have the best technical knowledge but Sonos do seem to make it super difficult to pair up with analogue and other devices - what harm it would do to add just one phono port or some way of connecting to the Sonos product I don’t know…I’m looking into getting a Play5 - heard there’s a phono in on that…otherwise I’ll get some separate speakers and screw the Sonos…unless there’s another solution 

I ripped my CDs using an external CD/DVD drive costing maybe £30 and stored the files on a NAS drive that cost £150:(and which has many more uses than just storing my music collection).

A few years on that has become almost redundant, as I can stream it all in CD quality using Amazon Music Unlimited. 

Maybe you have missed the point of Sonis and in saying 'screw Sonos' you might be screwing yourself?

A music streamer is completely unnecessary with Sonos. All you need is somewhere to store your files and /:or a subscription to a streaming service. Sonos will do the rest.