You’d still need a router to connect the BRIDGE to, even if your 4G was fast and broad enough to carry a signal. Sonos requirements state a wired connection, as I recall, so there’s no guaranty, but Sonos cant tell where the internet feeding the router is from, so I’d probably try it, with the expectation that the bandwidth may not be enough.

I honestly am happy to use without internet whatsoever and just run a line in 

I just want to get some tunes happening

You do not need internet to run a Sonos system, only on set up an internet connection is needed. So if you only play music from local sources (probably connected to the Play:5's, or from a local computer) internet on set up and from then on only a wifi connection would be enough. Spotify etc. is out of the quiestion when there's no internet of course….

unfortunately the 4g network I had planned is not available as it require my phone to hotspot can I do it without internet?

I do not understand. How is 4G not available when you have a phone? You state “can I do it without internet". Can you do what?

Is the problem you need another phone to command the system using the hotspot on the first phone?

sorry I didn't really explain well

I have 4 g on my phone 

But I have a bridge which I believe needs to be plugged into a router to work and create a wifi network even without internet 

in the past I have been able to creates and run the network in this manner without internet.

now I can seem to do this as it requires the app to be connected to the internet as well as the wifi network which I can't do

You will not get anywhere without a router to connect the Bridge to. The Bridge creates a network for Sonos. But you will also need a way to let your phone connect to the Bridge - a wifi network, whence the router. The router need not be connected to the internet. Please note that the Sonos devices will not be updated (because they are nit connected to the internet), so the Sonos Controller app on your phone must not be updated either - the software version on the devices and of the app needs to be the same.

I think it would work without the Bridge using two phones. Since you need a network that is accessible both by a phone and the Sonos devices, you could use one phone as a hotspot and connect the Sonos devices and another phone (that will carry the Sonos Controller app). In this set up you will not need the Bridge. The devices will update via 4G, so you can let the app update too.

I have a router attached to my bridge

it creates the wifi network the bridge enables my play 5’s  and sub to be part of the Sonos family

in the past thats all I ave needed as long as I do not upgrade my Sonos components or app

now because I am required to download and use the app on my phone to create the new Sonos network I can't be connected to the router network and the 4g on my phone at the same time

I can't set up my internet free Sonos/Router network

I have 2500 grand worth of Sonos gear and I can't even put a line in and play an ipod

the only way I can see around it is to buy a 4 g router with ethernet port and hope it works enough to set up system 

I can't even speak to anyone direct at Sonos Australia anymore like I used too its been farmed out to call centres who when I spoke to them couldn't even understand the above concept….

Maybe we're past due to get the facts straight:

• you have wifi from your router;
• the router is not connected to the internet;
• you have a working Sonos Bridge connected to the router;
• you are using the S1 Controller app (not the Sonos app, which is S2 only, see https://support.sonos.com/s/downloads)
• the Sonos devices used to function together and are not reset.

Are these the facts?

Then you state: “now because I am required to download and use the app on my phone to create the new Sonos network I can't be connected to the router network and the 4g on my phone at the same time”

If the above facts are right (especially the last bullet), you do not have create a new network - the Bridge does that for you. You can download the app on 4G and use it on your phone when you switch to wifi (at which time you lose internet access). But as long as you do not use internet sources for music (like Spotify) you are OK.

You state: “I can't set up my internet free Sonos/Router network". This does not give many clues to help you. Can you please state any error messages you receive while setting up the system? What does the app tell you? What happens when you try to set up or connect to the system?

One thing does spring to mind, that we could encounter later on: if you haven't used the system for a while, it's software may be out of date. Since you've redownloaded the app is has the newest software version. Than te system needs an update to.

But please brings some clarification on the above points first.

If you have a router that is still creating a WiFi network then you need to connect your phone to that, not to a 4g or any other mobile network.

Could you take all the kit to a friends and borrow their connection to update all units to latest software/ firmware?.

You may have to plug your router into theres to maintain the correct ssid that is stored in your speakers.

@powerhouse A right. So you have to sign in to Sonos via the internet while connected to the system, propably because you are setting up. This could be achieved by (temporarily) using another phone as a hotspot  and setting the system up on that hotstpot - foregoing the Bridge. Then the phone you are using the app on and the system are on the same network - but only if the scond phone really works as a router (so the system and the phone the app is on will be able to see each other), of which I am not sure.

Setting the system up in a place where there is an internet connection could be your best bet. But remember not to update the app on your phone after the first set up, because the software version of the app and the system needs to be the same.

The 4G router would also achive this, with a bonus that your system can be kept up to date.

@Keithmac Good advice, though with a Bridge there would not be an SSID stored in the system. Tha being said: Sonos advises against using the Bridge because it runs an older version of Sonosnet and, more importantly,  it's power supply is prone to intermittent failure because of age.