Mathematics behind it all.

Hello guys, I can never express just how much useful information that this forum and it's contributors has given me. I have seen countless posts of what I feel to be trustable designs and info. The one question I have though is what are the mathematic functions used in designing a studio? How does one calculate exactly what angle would be good to twist a wall for best reduction of early reflections, or what a wall's entire makeup would resonate at? I have seen some of the calculators,but what is the good hard math that powers it?

Blue, :) This question is soooooooooo general, too general. If you find a calculator, you mostly can find the math behind it on the net by googling for a related keyword. E.g. Sabine, panel or membrane damper, Helmholtz resonator, ......, ......, Pound power, dB calculations, .... You question about that wall. If you want to do that accuratly you can earn a degree in acoustics doing that. To know more, there isn't an other way than starting to read about it. There is one maniac (in the positive sense), who wishes to know and understand it all as well. That's Bob Golds, who at the moment finds studying the stuff more a hobby than building and finishing his home theater itself, which was his original intent, causing him to visit related web groups. In this thread his current library he bought already is listed. http://forum.studiotips.com/viewtopic.php?t=2178 :twisted: As a matter of speech you can build a studio for the price of the books he bought. :mrgreen: I wonder if he really read them all (or even can, there's some really heavy stuff included in that library)????? :) Hence you know where to start. Acoustics is a specific sub part of physics (and then I ignore here electro acoustics, psycho acoustics, ...... ). It's not a collection of 10 formulas to be found.

Thank you for the reply. I might check out a book or two from the thread posted to learn a bit more. The main thing I wonder is knowing the math on what degree to tilt walls in studio designs to create the desired effect. You say I can earn a degree in doing this accuratley, but realistically I would just like to understand it. Being told to build walls non-parallel to avoid standing waves seems too general to me. So Someone must know, what is the formula for calculating ideal wall angle? What terms should I research in Google for this at the least, without being too generic?

blue642 wrote:

........The main thing I wonder is knowing the math on what degree to tilt walls in studio designs to create the desired effect. You say I can earn a degree in doing this accuratley, but realistically I would just like to understand it. Being told to build walls non-parallel to avoid standing waves seems too general to me. So Someone must know, what is the formula for calculating ideal wall angle? What terms should I research in Google for this at the least, without being too generic?

Blue, In the traditional explenations in groups you will notice that angling walls is NOT mainly related to avoiding standing waves, since you have standing waves in ANY room of whatever shape, no matter how assymetric. There is a sticky topic here somewhere about standing waves and related animations. The angling relates to the distribution of the sound in the room, reflection free zone applications, bot mostly the traditional minimum 6° to better 12° per side is related to avoiding flutter, not standing waves. This 6° to 12° is an empirical value. If you should see the math of flutter, recognized in real live by anyone id and when it occurs, you'll notice it's a really complicated business. A lot of this relates to geometric acoustics, while small rooms are mostly dominated by modal acoustics. Now flutter is also modal, but with very short pulses in function of room sizes, not allowing standing waves to establish. But there is more to it. One can have flutter between more than 2 walls. The traditional description of a repetitive echo between parallel opposing walls is a bit too simple. Hence you maybe start feeling that you need to 1) either get a feel and insight for these concepts needing to study them, or 2) that you just have to accept the experience and combined knowledge from people in groups, who combined build lots of studios already proving/confirming the value of the followed approach. You will not find the simple formula you're looking for. If it was it was integrated in simple calculators already. Take notice that ALL these calculators are stylized approaches based on lots of theoretical boundary conditions. If you want to know you have to study it, systematically, and you will notice, as with everything else, the more you learn the more additional questions arise. Really simulating a sound field in a room calls for very complicated simulation software, mostly based on a numerical approach, not on simple analytic formulas.