Ethan Winer wrote on Sat, 21 February 2009 15:09 |
Was the wood on top of solid concrete?
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Yes.
Ethan Winer wrote on Sat, 21 February 2009 15:09 |
"The information we have" is the crux of it. I give much more credibility to the data shown in my report than to the data in the book Andre posted. First, the data I used to calculate reflectivity agrees with most other data I've seen. It also agrees with what I consider common sense.
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You do realise that there is considerably more info on the subject in the article submitted by andre than in any of your supplied data? It's also not a question of common sense but a question of understanding the data. What your data shows is what is also shown and explained as an exception in the Watanabe & Hayashi study: that, all other things being equal, under a certain thickness absorption becomes uniform and lowers. You can't derive a conclusion like yours, that "wood is no different than linoleum", based on the exception.
That would be common sense.
Ethan Winer wrote on Sat, 21 February 2009 15:09 |
the data in that graph disagrees with all the other data I can find.
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Because it's not the same data at all! Only parts of it bears similarities. Your data only shows (probable) reverb chamber measurements with thin layers - and again it was shown how that affects the results. The book shows much more in-depth measurements, with various samples in various conditions. Therefore it is normal it bears different results with "all the other data you can find".
Ethan Winer wrote on Sat, 21 February 2009 15:09 |
I cannot agree yet. Sorry!
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You don't have to.
But I can't help thinking you fail to see the forest for the tree here. What I expect from this discussion are not final, undeniable facts but to determine the most plausible explanation and to show that this is a complex issue that in itself prevents any straight definitive answer.
We can outline certain behaviours. Concluding like you do in your article is not okay by any remotely scientific standards.
Ethan Winer wrote on Sat, 21 February 2009 15:09 |
That's a great idea. Do we have data for wood on cement at various thicknesses
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I'll check in my database, but we do know now about the 10mm benchmark. That is a lot already! And this phenomenon is not linked to whether or not the wood is on cement or joists. Just thickness.
Ethan Winer wrote on Sat, 21 February 2009 15:09 |
Does re-emission happen with wood on cement, or only with wood on joists? Do we have any re-emission data? I agree that the more data we can see, the more complete the conclusion will be.
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Re-emission is a very, very tricky subject. Way more complex than the one at hand. What you need to know is that it's everywhere in any solidian that vibrates.
Ethan, your question has been answered I believe, by others and myself. We'll have to agree to disagree. My personal view is that your approach is lacking in many ways.
I am going to close that thread now. I don't think we can really go any further and I believe there is enough information for each and everyone interested to make up his own mind about it all - which is what matters.
To everyone, feel free to PM me if you have something relevant to add to the thread. I will then re-open it.