Sound deadening and insulation, whether purpose-made or simply walls/trees/incidental stuff. Fifty people in a 200sq/ft space will almost always louder than twenty-five people in two 100sq/ft spaces connected by a doorway.
Unless the space has amazing purpose-built acoustic qualities, put physics obstructions between groups of people (walls, doors, bushes, trees, fences, whatever).
If a house-party is unbearably loud, there's just too many people for the space, or there's some anomaly that is concentrating too many people in one area.
Unless the space has amazing purpose-built acoustic qualities, put physics obstructions between groups of people (walls, doors, bushes, trees, fences, whatever).
If a house-party is unbearably loud, there's just too many people for the space, or there's some anomaly that is concentrating too many people in one area.