diffusors=bigger sounding room?

[josha]

I understand that diffusors can make a small room sound bigger, but 'm finding it hard to understand how this works? Anyone able to explain the mechanics?

[Glenn Kuras]

see if the following helps

GIK Acoustics presents "How Diffusion Works!"

[Ethan Winer]

Originally Posted by josha

Anyone able to explain the mechanics?

A room sounds small when you can hear echoes that arrive very soon after the original sound. This aural sound clue makes the small size obvious because of the short delay time, and also because the echoes are loud. Versus a large room where the echoes arrive much later, and they're also softer because they travel farther through air which attenuates volume. Yet another size clue is comb filtering, a specific type of skewed frequency response that happens when a direct sound and an "early" arriving echo combine.

Both diffusors and absorbers can reduce the effect of these clues. For example, a wall that absorbs 100 percent is acoustically the same as a wall that's infinitely far away. Either way, the sound goes out and never comes back.

The difference between an absorber and diffusor is the diffusor scatters the reflected sound to other parts of the room rather than just get rid of it. So in a room that's totally filled with diffusors the sound will go around and around a few times, striking multiple surfaces, on its way to your ears. The longer the sound bounces around, the longer the delay times, which is similar to having plain walls farther away.

--Ethan