Hi Avro RJ,
You can connect stereo Beolab speakers (eg. Beolabs 4000 mk.1, 6000, 8000, etc) to a receiver with pre-out sockets using these cables (one set of cables is needed for each pair of speakers to be connected):-
If you have a Beolab 2 subwoofer, or a Beolab 7-x/Beolab 10 dedicated centre speakers, these each need a powered cable to generate the trigger signals that would normally be sent from a B&O television:-
Location: The cable workshop, England
My B&O Icons: