Dis Ohana,
If it helps, think of it as 3 levels. A 'pit' = main floor, level 1 = raised area, level 2 = second floor
When we went, the main floor (pit) consisted of long rows of tables, almost like a huge picnic setup, that bumped up (perpendicular) against the stage. Around the perimeter of that, there were high tables, I would call them cocktail tables except they had tall seats for sitting. We originally were going to sit at the 'picnic tables', but decided when booking to sit at the high tables. We had no problem with the speakers, but weren't overly close to any where we sat. Outside of the main floor area (pit), there were tables around the railing, but I don't know if they were in use during the Gospel Brunch, since the omelet stations and some food areas spread out on the sides as well.
For the lowest noise level, I would guess it to be the second floor area, if the distance to the buffet is not a problem for your party. If you want the ground floor level, then the high tables worked fine for us. I would stay away from the picnic tables at all costs: they were closest to the stage, and navigating down the long row to ones seat could be a challenge at times. Lots of clapping and singing there, and some seats were very close to the stage indeed.
All that said, this was my recollection from years ago. The layout may have changed.
Please let us know your thoughts on the whole experience, when you get back. There aren't alot of reviews out there, on this event.