The group is broken up into seven groups and the rooms share walls. One class inevitably gets started before the one next door and gets to the three ohms and invocation before the other group. Depending on when the room next door gets started, it can almost sound like a round. And the singers in all the classes Ive been in are LOUD. Its a noticeable difference. Of course, the room Im used to singing in is quite a bit bigger and the students are usually spread out more. Still, here, it seems like the yogis are quite loud, blowing away the caller from that first ohm to the last.