I would suggest that it's pretty far off. The peg board has a mid band absorption quality and quite a bit of diffusion, the dropped ceiling produces a big bass sink and high frequency absorption. To model this correctly you need to put in the sub floor (above the dropped ceiling) as the true ceiling, then add the ceiling tiles as a "hovering" layer below them. You should not use any of the things that CARA has in their database, but rather get the data on the ceiling tiles and use the material editor to build that material. If you don't know the data on the ceiling tiles I suggest getting a copy of the book "A compendium of materials for noise control" It was published in 1980 by our government and is out of print, but many libraries still have a copy. It will give you the absorption coefficients for just about any material at a variety of frequencies.
ceiling model material for Cara?
I am trying to get the baseline model for my listening room set in Cara. As some of you who have used this tool know it is sometimes difficult to pick the material from the list that best approximates what you have in you room. What have others used for the best fit for your average drop ceiling tiles. Mine are made by Armstrong, that's about as much as I know about them.
I'm not sure if the Acoustic Board material model is correct for the ceiling. If it is, I have a lot of work to do in the HF area!
I'm not sure if the Acoustic Board material model is correct for the ceiling. If it is, I have a lot of work to do in the HF area!