Room Mode Calculator and Converter

[Doug Plumb]

It depends on what you mean by similarities - you always have to verify a simulation with a measurement. Those two are many dB off - the dip is predicted but not exactly in frequency.

[brucek]

blaser says:

Look at my room theoretical subs response graph vs practical measurements....Can you see any similaritires?

Yeah, interesting. The peaks and dips appear to line up, and if the vertical scale was the same they'd be quite close. It's nice that the measurement verified the simulation.

There are always lots of influences in a room that will change the actual meaurement, but if you've got a rectangular room, there's a good chance the resonance calculators will give some decent indications where the modes are and whether they'll line up or not. Certainly useful in finding the optimum room shape for home theatres or listening rooms if you happen to be building one.

brucek

[Blaser]

You're correct Doug. A similation will not tell you everything very accurately, but it gives only an idea. BTW, I am sure I could get closer to practical measurements by increasing the no. of reflection (as my room has brick walls) that I have quite ignored.

Here is another SIMULATION which made me decide not to chose the nearfield arrangement in the same room because I like a steep house curve.
I know there will be a dip around 30 Hz, but measurements might show that dip propably more or less enphasised with a propable slight change in frequency. But the concept is still the same...There will be a Dip with this configuration at a frequency low enough to be unpractical for a house curve without overstressing amps/drivers...

This is what I beleive to be the real intention of such room calculator programs.

[Blaser]

brucek wrote:

Certainly useful in finding the optimum room shape for home theatres or listening rooms if you happen to be building one.
brucek

DEFINITELY! I wish I knew this before constructing my House

[Eric Desart]

franman wrote:

The bonello criteria is based on Axial mode distribution but we look at Oblique and Tangential modes as well, as they do help "fill in" the areas above the fundamental for each dimension in small rooms. Hope this makes sense....

Just a small comment, since I accidentally stumbled upon this post by Googling.
My idea is not to discuss this but to correct something.
The Bonello criteria are based on all modes not on the Axials alone. Hence taking the tangential and oblique modes into account is integrated in Bonello's approach/calculation method.

Just info.

Best regards
Eric

[Blaser]

Welcome to the shack Eric,

Hope to see you intervene more !!