If a room feels loud, harsh or hard to talk in, the cause is usually that sound keeps bouncing around after it has been made. Hard floors, bare walls, a flat ceiling and big windows reflect almost all of it back. People then speak louder to be heard, which makes the room louder still. Acoustic people call this reverberation, and it is the single most common reason a perfectly nice room is unpleasant to be in.
How to tell if it is your problem
Clap once in the middle of the empty room. A short, dry clap that dies at once means the room is fine. A ring or a tail that hangs in the air for a second or more points to too much reverberation. A second sign is behaviour: people leaning in, raising their voices, or leaving early. If guests keep saying a place is “too noisy”, the room is often the reason, not the crowd.
What actually helps
Soft, porous surfaces take sound out of the air. The ceiling is usually the best place to start because it is big, clear of furniture and in direct view of everything in the room. After that come walls, then floors. Curtains, upholstered seating and bookshelves all count for something, and a full room sounds quieter than an empty one for the same reason.
What does not help
Egg boxes and thin foam tiles do very little for speech. Treatment that is too small for the room, or in the wrong place, gives you the cost without the improvement. And absorbing sound inside a room does not stop it passing through a wall. That is a different problem with different solutions.
How much is enough depends on the room
A classroom, a café, a meeting room and a worship space all have different targets, and in some countries the target is set by a published standard. Echo, from AcoustaPLOT, predicts how much your particular room echoes, compares practical ways to reduce it, and gives you a report to take to suppliers, so you know what to buy and how much before you spend anything.
Echo is an indicative design guide, not a guarantee of performance or a substitute for a consultant where one is required.