There are small 1:1 loop devices that can be used on table tops and they can be linked to one or more external microphones. The "boundary" mic can be daisy-chained to cover a long table and allows for any speaker's voice to get piped to all of the telecoils in the "loop" field. Loop designers/installers can get very creative with where they install the cooper coil loop that creates the audio field -- under a table or counter, overhead in a ceiling tile, overhead in a hanging disc, under a floor mat, or within a seat cushion.