I keep watching your videos picking up knowledge and then I go back and re-watch videos I have previously seen and I understand better than before the concepts presented. I wish more RU-vid presentations were done this way in other knowledge based topics. Keep ‘em going Dennis! Thanks.
Thank you Dennis, and yes this video, as always helps. I keep reading/hearing that the room is 50% of the sound of a hifi system. In my experience 90% is a more accurate estimate.
Unfortunately too many people (myself included) have spent 100% gear and 0% Room Treatments. As a retired music educator, I’ve dealt with performing groups who had to deal with playing in basically untreated venues. As a performer on my personal instrument, there were particular stages in recital halls that I just hated the sound quality I had to endure and now I have a better understanding of why I was “disturbed” by my perceptions. A “pretty” room does not make for good acoustical properties. I think too many architects just use a few room dimensional concepts, throw up some nice looking panels, and call it done without ever checking the acoustical qualities of their work.
How is it, that all these albums were mixed with NS-10’s, no sub, which puts out hardly anything below 90 hz, yet they still translate and still have good low end?
Yes, talented people are talented for many reasons. One is an innate ability to perceive and act creatively. Another is the skill set to work around room issues that have a negative impact on their product..
How are you differentiating diaphragmatic from membrane? Membrane can have a "solid" membrane like wood. Doesn't have to be a flexible material. What matters is it having a sealed cavity like you mention with your ACDA. To me that's a membrane absorber. Diaphragmatic is when there isn't a sealed cavity like the GIK range limiter panels
If you examine the "membrane" absorbers in the marketplace, you will notice that the cabinets they use are lightweight. Most of these units have total weights in the 20 - 30 lb. region. They have a thin layer of material or membrane across the face. Most are filled with building insulation. They lack the proper rate of absorption per square foot to deal with double digit low frequency pressure issues. Anyone can build a box that goes down to 40 Hz. The trick is to achieve high rates and levels of absorption for every square foot of surface area. This is accomplished by using a better design. A diaphragmatic absorber uses much more mass to achieve its performance. Our ACDA series weighs in at over 200 lbs., has 2 front diaphragms that work together and an internal carbon fill that increases rate of absorption. Our ACDA series absorbs 35% / sq. ft. at 30 Hz. and 63% at 40 Hz. and a 100% at 50 Hz. There is no membrane absorber that can achieve these results.
Hello Dennis and thank you so much for sharing all this incredible knowledge. You mentioned in one of your videos, that you get your carbon material from UK - where specifically? Best regards!
Dennis, I have an exposed 2x4 stud frame in an existing 10x20 ft garage for drumming studio. Im interested in using stud bays to accommodate carbon filters. Would you suggest I increase the stud bay depth by stacking and securing an inner 2x6 or 2x8 frame up against the existing 2x4 frame to provide the required bay depth? Or better to leave the wall frame alone and build stand alone movable ACDA units / drum platform? Thank you
Great video. The physics is everything, and is too often ignored. I wonder if carbon prices will ever come down to make these low-end treatments more affordable. Or are they going up?
Any good recommendations for books? I've read the master handbook of acoustics, but it lost some weight with me after I got to the section on treatment.
Dear Dennis, thank you for this video. Does the 170 constant in the formula relate to metric as well or should one use a different number when calculating density in Kg/m3 and depth in m? All best, Robin
