Klaus
At Coventry Meeting the person who installed the system in the main big room said that there probably was no need for anything in the smaller room as because of its size and closeness of everyone it would probably not be a problem.
So do you really need anything in a small room? The loop system is great to pick up speech when it is fed into a loop. otherwise normal hearing aids work well.
We were given a small portable system. that fits into a suitcase so we can lend it and it feeds into a mat aerial . The person needing the hearing support sits on a chair or adjacent This worked very well for a 'granny attending a school play'. However, that last point does not answer your direct question.
William Waddilove