Recent content by kvalsvoll

This RT60 often ends up in a discussion of semantics, and once we establish this definition of RT60 as a measure that can't mean anything in small rooms, we can still continue to use it, as a measure of how fast the sound decays - in any size room. I find the Decay graph - like the one in #4 -...

Looks good to me, quite short decay for this room that is larger - 9m is quite large, for domestic rooms.

Possible you need to update your REW software, this is taken from the "RT60 Decay" window. Button between RT60 and Clarity, on the top.

Exactly.

Looks like this, and I will try to explain why these RT60 numbers are not usable for describing the acoustic properties in a small room: These RT60 numbers are meant to be a measure of how live the room is, so we can have a simple single number describing the acoustic properties of a room. But...

Decay is much more linear across the frequency range, initial early decay is much better, in the 100hz-1khz range.

This is a ceiling absorber cloud.

The room is w-l-h 3.44m - 4.41m - 2.22m. From the 3d model (made by the owner) we see that the absorbing area covers the whole front wall (exclusive room for subwoofer units) and a large part of the back wall. The room is quite small, but large enough to contain sufficient acoustic treatment...

The back wall absorber is 400mm thick - 40cm. 1ft equals approx. 30cm. Wood fiber insulation, acoustically similar to rockwool. The front wall is 200mm/20cm thick absorption. Wood fiber insulation, acoustically similar to rockwool. Here is the "before" decay - same scaling as the decay graph...

Just to clarify; my company does not sell acoustic treatment products, and we do not provide a paid service for acoustic room design. The principles behind this room design are to be considered as known, generally available knowledge that can be used by anyone who wants to improve room...

"Before the treatment, certain low frequencies was very dominant, and no matter EQ's applied, the result was not good." Fixing room acoustics is no longer a never-ending journey with experiments and trials and unpredictable results - how to do it is known, how it will measure when it works is...

Not strange, since the noise floor often is around -50dB in a typical measurement. I just checked several measurements form many different rooms, and they all lie around -50dB noise floor. Though you may be able to get more dynamic range by increasing the spl for measuring, I don't see any...

I also must say that this is only a suggestion for a minor improvement, it is not by any means a requirement. Until recently, this graph window - RT60 Decay - did not even exist, I have found it to be very useful to visualize acoustic properties of a room.

I agree it may be sufficient to have a fixed range. I do not have any problem with using 60dB/1s. If the 60dB and 1s are minimum limits, then perhaps changing the range to one fixed value would solve the problem. Some measurements end up with -70dB range, I have one -100dB. Bwfore pressing the...

In the "RT60 Decay" window, top graph, the vertical dB scaling should either be fixed to a suitable range (0 or slightly above -> -60dB), or configurable. As it is now, the vertical scaling changes for different measurements, and this makes the graphs more difficult to compare. Also, it may...