Hi.  You say you are looking at Sonos for a multiroom solution, but only one speaker would actually be Sonos?  Much as it pains me to say it, if you want to keep mostly third party gear you should probably look elsewhere, e.g using Amazon Alexa or Google Home devices to link things up.

Others may have different views.

First, what do you mean by multi room - do you really have a use for all speakers in all rooms playing the same music at the same time? Sonos does this best, but is worth the spend only if that need exists.

PS: which isn't to say it does not do other things well, just that there are other solutions that also do these, many at lower prices.

Thanks @John B 

Hoped it would be possible to choose Sonos as I like their app, and have heard good things about the reliability of the system. However, it seems they only want to bundle the multiroom system with their own speakers, which are not the same level as e.g. B&W. That is unfortunate.

Thanks @Kumar 

Would prefer to have all speakers in different rooms playing the same music at the same time, and more importantly be able to control all of them through on single app.

I thought Sonos could do this for me without committing to only use Sonos speakers now and in the future.

That isn’t what I was saying, and I apologise for the lack of clarity.  Sonos is very good at integrating third party amplifiers and speakers.  In fact, when they launched that was the only option.  I have a ‘traditional’ HiFi system that is incorporated into my system using a Connect, the predecessor to the Port.

But as you said, the Port seems overkill for the B&W - but it is an option and would, I am sure work fine.  (It is the only option for bringing the B&W into Sonos.)

The Connect / Port have always seemed very expensive to me for the job they do, but if you want a great result they will give it to you.  I think there are options out there that would give you almost as good for quite a bit less.  Sonos really scores with sound quality, but you are hardly using that.

One other thought: a Sonos Five isn’t that much more expensive than a Port and is a great speaker.  You might want to try it out and compare it with the B&W.

If there’s already a Port -- to feed the existing amp -- there’s always the possibility of hooking a long-range Bluetooth transmitter to it as well, to serve the Zeppelin.

Note that the Zeppelin wouldn’t be in sync owing to the BT delay.

A coax-to-optical converter plus an Avantree Oasis would send aptX BT audio over most of the house (or Oasis Plus for aptX-HD future-proofing).

Playing music in perfect sync across speakers/rooms works as well and in a slick way as it does for Sonos is because of the kind of bundling you refer to and the statement that Sonos speakers are not at the same level as B&W is debatable. More to the point, via the use of units like Port/Sonos Amp, the use of third party amps and speakers IS possible - as long as these have line level input jacks or speaker terminals.

I noticed that the B&W is airplay compatible as are all the speakers in the current Sonos lineup.  Although perhaps not ideal, you could use airplay for the times when you want all 3 of your zones/rooms playing audio at the same time.   You wouldn’t have full control through the Sonos app, and would limit your sources to what you can stream through an Apple product, but it’s an option worth considering.

I also think that you might find Sonos speakers on par with your B&W, or better. Although it costs more than your B&W  a stereo pair of Sonos Ones likely would be better, if for no other reason that stereo separation.  And the pair would be cheaper than a Port.  Maybe the plain would be to start off with a Port and SL for your kitchen, then decide how best to deal with the 3rd room.