To add.. you can get that type of pad sound on just about any synth. A Triton, EX5, Motif etc.. just about any rompler/workstation could do it. I would also say VAs or Analogs, but their stuff has more of a half sample half modelled sound to my ears.
By the way.. they definately play a Voyager, but I think it's just for show and they actually use it to trigger a polyphonic synth. I don't really hear anything on the newest album which sounds like a Moog to me.