You need a Neutrik Speakon two conductor cable. The old connectors we used were four conductor cables to work with the RHH and earlier Neo cabinets.
RAG
Does this mean the new Neo IV cabinets won't work, or won't be able to use the bi-amp function, with an older RB head? I'm thinking of upgrading to GK Neo cabs with my 1001RB-II head. Should I look into older Neo-II models?