This is possible but depending on the brand of speakers and amp you will need a device to answer the call. For example if you have Bogen equipment you need the UTI1 to connect to the FXS port on UC320 and then to the amp.
The ATA186 is a Analog Telephone Adaptor, in other words it is, as you appreciate just a device to extend FXS connectivity to a traditional Cisco Phone system.
Mario, mentioned a Bogen device, I have used a device like a VALCOM 9970 to connect a amplified speaker to a phone system.
As the manual for the VALCOM 9970 says from a screen capture below, it provides ring trip In other words it answers incoming calls and then amplifies the signal over a amplified overhead speaker. There are however many devices out there that can be used, and in no way am I pushing the VALCOM device, it just Valcom lent me one for validation purposes. There are however many devices out there that can auto-answer a FXS connected call and amplify that incoming FXS call audio over powered speakers.
If you did need to expand the number of FXS ports on a UC320W, you would need a SPA8800 and not a ATA186, but still need something like the VALCOM or Bogen device connected onto a FXS port..
As a example , what follows is the screen capture of a logical diagram taken from a VALCOM manual showing how the VALCOM 9970 is connected , this is a valcom document, but added some text in red.
David, thank you. In the past we used a ATA plus a Bogen TAM B device for a CME to connect to a large system. With a amplified paging system it is not possible to just make a direct connection from FXS to the paging system? I will look into this Valcom device.
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