In a very technical sense, neither copper not fibre require a voice service for a broadband service to work.
Unfortunately, that technical sense is not what happens in the UK, with BT-supplied services, right now. When you want broadband from them, it must be added on top of a voice service. The back-office (ordering, testing, monitoring, fault-handling) systems (I guess within BT Wholesale) require this.
FTTP puts some complications in the mix, certainly. In some locations, FTTP overlays copper - and the voice service is likely to remain on copper while the user gets to choose a broadband service - ADSL over copper, or GEA over FTTP. In locations with just fibre, the voice circuit becomes another set of packets on the fibre.
Openreach themselves do allow FTTP to be ordered for just broadband ... but they charge more for it when ordered standalone. In fact, so much more, that it ends up the same price as when you order both broadband and voice connections (irrespective of the voice connection method).
You will find it hard/impossible to order FTTP without a voice service.
BTW are gradually starting to trial a new product known as "WBC SOGEA" which removes the requirement for a voice line with FTTC - so requires a re-write of all those back-office systems. Don't expect it to be fully available for a couple of years; the changes, of course, ought to apply to FTTP as much as FTTC, but who knows whether that will happen...
With FTTP, you will not need a "cable modem" or indeed any kind of modem; Openreach supply their own optical ONT to fulfil this role.
You will need a router - which only needs wireless capability if you want to access the router over wireless. It will need to be able to connect to Openreach's ONT - which usually requires a "PPP over Ethernet" capability - so the "WAN" connection port will be a full Ethernet RJ45, rather than a bare DSL/phone line RJ11 port.
Before FTTC came along, this kind of router was commonly known as a "cable router", because it wouldn't work with DSL at all - it was only a router, with no modem component. Once FTTC came out, with Openreach-supplied modems, it required routers of this form too, so the label "cable router" is something of an anachronism, but is still widely used.
Edited by WWWombat (Thu 19-Nov-15 10:12:42)