One of the most difficult things to deal with in church sound is the choir monitors. There seems to be no really good way to do it. Tonight I was in a church in Florida that has a fairly large traditional-style auditorium. The monitors were a part of the center cluster hanging from a very high ceiling, and a couple of problems became apparent right away.
First, the monitor was heard throughout the auditorium. Because this church prefers a quieter mix in the mains, but the choir wants to hear the monitors at a fairly loud level, the monitor became the prominent source in the house. This is quite common in churches and results in a very boxy and indirect sound throughout the house. Clarity suffers and it just plain sounds bad. Unfortunately, this is one problem that is not fixed without some re-training of the performers. The only solution without bringing the monitors closer to the performers (such as with hotspots or ear monitors) or boosting the volume in the mains, is to run the choir monitors at a lower level. This forces the choir to pay attention to the director more closely--which may not be all bad. The choir will most certainly give you grief and tell you they CANNOT HEAR THE TRACK AT ALL, but it is worth weathering the storm. They will eventually get used to the lower volume and learn to sing along with confidence.
The second problem tonight came because the speakers were so high in the ceiling. The choir was singing with soundtracks that were played through the ceiling monitors. The singers were slightly behind the track because of the distance the sound had to travel to get to them. Their voices traveling to the microphones, which were quite high as well, added even more delay. By the time everything reached the audience, there was a significant delay in the vocals as compared to the track and it became distracting. The best solution here would be to get the monitors closer to the singers--and probably the mics as well. There are some speakers that do a good job of throwing the sound in only one direction, but a concern they do not address is the sound that is bouncing off the back wall or being picked up in the rear patter of the hanging mics.
Convincing the choir director and members that they really do not need as much monitor as they are currently used to is a necessary step toward better sound in the house. It is not easy, but it can be done with time.