Merging DMX is one of the most processor intensive operations in DMX - well it is if it is done correctly. There are a load of cheap merges on the market using washing machine processors and parts borrowed from the local tractor factory, buy one and enjoy the audience asking for their money back. XTBA merges are built to last, which is why we can guarantee them for life!
From two into one, two into two and four into two mergers (3 of which did service on the feature film City of Ember - don't ask why, we don't know!) XTBA should have a merge to keep your lighting data secure and correctly merged. All XTBA merges have address switches that allow for one (or more) DMX universes to be offset allowing data to be overlapped or desks joined 'end to end'.