That is a viable methodology for lower frequency noise transmission. You must add aditional material types for middle and high frequency noise attenuation.
Very interesting. However that amount of weight would be too much for an apartment in a building. As well as the space required. This seems targeted at studios and commercial settings with high requirements and space available (as well as cost). What are your thoughts on steel and lead? Cheers
@@AcousticFields My understanding was that lead is toxic to handle bare handed and if there is air exposing or connecting to where one breathes. If it is sandwiched and well sealed no amount of off gas or the like would reach the interior or the exterior for that matter. Also I think being more dense and softer than steel it's better for low frequencies. But the cost is higher for the same mass like 3 or 4 times as much. I would think it is much easier to handle and work with than steel (for cutting, moving, soldering etc.) specially if thinking of 1/4 to 1/2 inch steel as opposed to thinner sheets. Anyway, everything has a price as far as pros and cons. Steel and lead allow for less space but are more expensive than regular materials. Nice thing is steel is bulletproof.
Hi Dennis, do you have the Transmittion Loss data of examples shown in the video? STC and the behavior in frequencies below 100 Hz? Thank you very much!
Hey Dennis I was just sittin here thinkin, if the idea of a studio is to have no reflection, then wouldn’t a round or circular room be ideal or could it perhaps cause even more problems than the average rectangle ?
The idea is not to eliminate all reflections. That would be an anechoric chamber. Anechoric means reflection free. A reflection free room is used for testing sound sources such as speakers. If the engineer can eliminate room sound from the equaltion, they can focus on the product numbers without having to weed through room distortions. We need both direct (straight line) energy from our sources and room reflections in order to perceive the sound quality as realistic. A circular room would produce reflections that would tend to focus on the circle center and eliminate our ability to hear the wanted, direct energy from our loudspeakers or other sound sources .
Hi Dennis, just a quick thought on describing the interactions occuring from "garbage truck" to ear drum, Walls can be described with conventional T/S parameters, reacting to external energy impulses depending on frequency and amplitude, absorbing these energies can be treated just like ANC?? would love your thoughts on this analagy!! thanks mate
I dont think absorbing is the correct verb to use here. Noise transmission should be renamed to vibration transmission. We are really reducing vibrations through a process, but I dont think we can call that process absorption in the normal sense. Based upon my experience and study, we are attenuating vibrations. I do not think sound absorption processes would be at play here. Vibrational acoustics seem to have their own domain with its associated "rules" which do not overlap with the absorption processes that I can see.
I see offerings for carbon and foam panels. I am curious to know more about the Vinyl material used with the sandwich. I am going to assume it is 1/4" mass loaded vinyl?
The sandwiches provide two functions. They provide an increased density for the rear "wall" of our diaphragmatic absorber process which increases the rate of absorption and they reduce vibrations which lower noise transmission.
Hey Dennis, how about walls filled with sand? Not sure, but I've heard it works very well. Curious to see what you think- cheers
That is a viable methodology for lower frequency noise transmission. You must add aditional material types for middle and high frequency noise attenuation.
I have seen a motel built in the 1960's with concrete block walls filled with sand between each room.
What about the thin sand-filled cardboard used in Wolf Bavaria’s Phonestar?
Very interesting. However that amount of weight would be too much for an apartment in a building. As well as the space required. This seems targeted at studios and commercial settings with high requirements and space available (as well as cost). What are your thoughts on steel and lead? Cheers
We use steel many times for noise transmission issues. Lead is toxic.
@@AcousticFields My understanding was that lead is toxic to handle bare handed and if there is air exposing or connecting to where one breathes. If it is sandwiched and well sealed no amount of off gas or the like would reach the interior or the exterior for that matter. Also I think being more dense and softer than steel it's better for low frequencies. But the cost is higher for the same mass like 3 or 4 times as much. I would think it is much easier to handle and work with than steel (for cutting, moving, soldering etc.) specially if thinking of 1/4 to 1/2 inch steel as opposed to thinner sheets. Anyway, everything has a price as far as pros and cons. Steel and lead allow for less space but are more expensive than regular materials. Nice thing is steel is bulletproof.
Hi Dennis, do you have the Transmittion Loss data of examples shown in the video? STC and the behavior in frequencies below 100 Hz? Thank you very much!
Our noise data is proprietary. We guarantee our noise transmission performance from 30 - 20K. in all of our new build proects.
Hey Dennis I was just sittin here thinkin, if the idea of a studio is to have no reflection, then wouldn’t a round or circular room be ideal or could it perhaps cause even more problems than the average rectangle ?
The idea is not to eliminate all reflections. That would be an anechoric chamber. Anechoric means reflection free. A reflection free room is used for testing sound sources such as speakers. If the engineer can eliminate room sound from the equaltion, they can focus on the product numbers without having to weed through room distortions. We need both direct (straight line) energy from our sources and room reflections in order to perceive the sound quality as realistic. A circular room would produce reflections that would tend to focus on the circle center and eliminate our ability to hear the wanted, direct energy from our loudspeakers or other sound sources .
@@AcousticFields ahh ok I should have known that you’ve said it many times before. Thank you for your answer sir.
Hi Dennis, just a quick thought on describing the interactions occuring from "garbage truck" to ear drum, Walls can be described with conventional T/S parameters, reacting to external energy impulses depending on frequency and amplitude, absorbing these energies can be treated just like ANC?? would love your thoughts on this analagy!! thanks mate
I dont think absorbing is the correct verb to use here. Noise transmission should be renamed to vibration transmission. We are really reducing vibrations through a process, but I dont think we can call that process absorption in the normal sense. Based upon my experience and study, we are attenuating vibrations. I do not think sound absorption processes would be at play here. Vibrational acoustics seem to have their own domain with its associated "rules" which do not overlap with the absorption processes that I can see.
I see offerings for carbon and foam panels. I am curious to know more about the Vinyl material used with the sandwich. I am going to assume it is 1/4" mass loaded vinyl?
Yes. MLV stands for mass loaded vinyl.
Hey Dennis, I notice in these sandwiches adding the mlv eliminates air flow. When does it matter for air flow to pass? Only in the carbon filter area?
The sandwiches provide two functions. They provide an increased density for the rear "wall" of our diaphragmatic absorber process which increases the rate of absorption and they reduce vibrations which lower noise transmission.
Have you tried creating a vacuum pocket instead of air? Sound waves cannot travel through a vacuum.
The manufacturing costs to create a vacuum would make the product costs prohibitive.