vasubandu Posted January 25, 2018 Author Share Posted January 25, 2018 OK first, how are we going to measure? Well, there is a standard. ASTM C423 - 17 Standard Test Method for Sound Absorption and Sound Absorption Coefficients by the Reverberation Room Method ASTM is an international standards organization. The Roxul 60 Technical Data sheet cites 10 ASTM, including 423. You can see it here. The reference is at the bottom of the page. For NRC, which I believe is an average of some kind is says .95 for 2" and 1 for 4" NRC for the SoundPLy material is .95 or the same as Roxul 60. SoundPly LR panels come in either 1” or 2” thicknesses I don't see a specification on their performance numbers, so I will assume 2" That would make them equivalent products, at least in the average. I don't have the breakdown like you do for Roxul. I am not sure what the roxul looks like. It certainly is worth looking into Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted January 25, 2018 Share Posted January 25, 2018 http://www.gikacoustics.com/wp-content/uploads/2015/09/GIK-242-Acoustic-Panel-Datasheet.pdf This is what I'm referring to. Notice the graph at the bottom. It shows absorption vs frequency. Quote Link to comment Share on other sites More sharing options...
vasubandu Posted January 25, 2018 Author Share Posted January 25, 2018 2 minutes ago, CECAA850 said: This is what I'm referring to. Notice the graph at the bottom. It shows absorption vs frequency. Their data sheet shows it numerically too, and I cannot find the same for SoundPly. I had not thought about that, but you certainly have identified a question that needs to be answered. Have you ever used Roxul 60? If so what is it like physically? Could you cut it? Quote Link to comment Share on other sites More sharing options...
RoboKlipsch Posted January 26, 2018 Share Posted January 26, 2018 find me numbers surpassing roxul 60...tested numbers then we compare. u are getting sucked into marketing. theres a cost value to it http://www.bobgolds.com/AbsorptionCoefficients.htm is a handy reference but heres the cheapest best source imo https://www.atsacoustics.com/page--Selecting-the-Right-Acoustic-Material--ac.html look at the ratios and costs nothing comes close at a dollar a foot theres no magic...its science and theres nothing 1" thick that absorbs low well even 2" is just decent, thus why 4" is considered the minimum for broadband Quote Link to comment Share on other sites More sharing options...
garyrc Posted January 26, 2018 Share Posted January 26, 2018 10 minutes ago, RoboKlipsch said: theres no magic...its science and theres nothing 1" thick that absorbs low well even 2" is just decent, thus why 4" is considered the minimum for broadband My old 4" was rated down to 450 Hz. Quote Link to comment Share on other sites More sharing options...
RoboKlipsch Posted January 26, 2018 Share Posted January 26, 2018 at 3" roxul 60 is .78 at 125 at 4" it hits even higher i made my entire theater out of 2 for front wall and sides and 4" traps in corners, at bottom of front wall and ceiling even 2" makes a big difference but what i could measure showed plenty of top end decay reduction the key is lots of 4" panels. hard to overabsorb down low BUT somewhat easy to overabsorb the top thus using 1" or 2" panels only to treat can cause issues...the bass lingers and the high end is dead but if you trap enough bass its a flipping miracle😁 you can listen loud without fear of weird sounds resonating or ringing Quote Link to comment Share on other sites More sharing options...
Khornukopia Posted January 26, 2018 Share Posted January 26, 2018 2 hours ago, RoboKlipsch said: I mentioned earlier that roxul 60 is the best sound absorption product. I have several hundred pounds of Roxul installed in my home theater as 24 X 24 X 48 bass traps. It works. The mineral wool batts are fairly easy to cut with a long serrated blade knife if you need to make smaller shapes. Other sound absorption or diffusion products have their purposes. The SoundPly micro-perf panels are a very interesting design. https://www.soundply.com/rf-series/ I first learned about them a few months ago, while I was researching pre-finished wood veneer wall panels. I have not seen or heard any SoundPly yet, and imagine they are pricey, but hope to see an installation in a fancy concert hall somewhere. 1 Quote Link to comment Share on other sites More sharing options...
RoboKlipsch Posted January 26, 2018 Share Posted January 26, 2018 you will notice basically no absorption at 125hz until a 1.5 or 2" panel is used sure they "microperf" them and have nice finishes but the numbers dont lie a $10 2inch roxul board has better numbers than any of those there are so many companies trying to market a basic technology as space age amazing read the .pdf file and lo and behold the core is glass wool the same thing owens corning 703 is....hmmmmm same "technology" as every acoustic panel....same substance and equivalent to rockwool just my strong 2c Quote Link to comment Share on other sites More sharing options...
vasubandu Posted January 26, 2018 Author Share Posted January 26, 2018 3 hours ago, RoboKlipsch said: theres no magic...its scienc And science seems to prefer micro perforations. I don't know know the answer but U have an open mind. Quote Link to comment Share on other sites More sharing options...
CECAA850 Posted January 26, 2018 Share Posted January 26, 2018 9 hours ago, vasubandu said: And science seems to prefer micro perforations. I don't know know the answer but U have an open mind. And science says there's no way it'll absorb bass. Quote Link to comment Share on other sites More sharing options...
RoboKlipsch Posted January 26, 2018 Share Posted January 26, 2018 My basic education in panels came from avsforum which has a 400 page thread with full time experts in theater installation providing a lot insight and advice for dedicated theater builds. Combined with measurements of my own it became clear theres no magic sauce, just materials and placement. With that said a pro like Erskine does spec for his clients a certain brand he prefers but even those still have a core of the same basic materials. Im passionate about treatment because when used, honestly even poorly, it makes the most dramatic improvement to a a room that any component can provide. Since they last a long time i see no issue buying from a reputable company vs building diy. For me on a limited budget i found i could build 3x or 4x the number of panels myself as i would have bought from a vendor and once i started using them I quickly realized i wanted a lot ☺ Quote Link to comment Share on other sites More sharing options...
Joe01880 Posted January 26, 2018 Share Posted January 26, 2018 [mention=61891]Joe01880[/mention] I wold really like an OLED TV, but they are expensive and it is hard to get around that, and they only go to 65 inches unless you want to spend crazy money. I can get an 86 inch LG with a good but not great picture for $2,400 delivered, and the kids will be more excited about big than great colors. A 65 inch i=TV is 57x32. An 86 inch TV is 75x42. That is 72% more area. Think of it in our terms. Would you rather have a really excellent bookshelf speaker or an OK 6-foot tall tower? Oh, wait, bad question. Ignore that. I saved for a year for my OLED. I also went thru my collection of electronics that are in perfect condition yet no longer used and are boxed up taking up space in my basement and sold them cheap. The money added up fast.I also looked at apps like letgo, FB Market Place and CL for people selling things like speakers WAY to cheap, bought them and resold them fast. In one instance I bought a set of A Cambridge Soundwork towers for $20, personally I thought they sounded like crap but I resold them the very next day on a different site for $150. Combine that with saved BB gift cards and in a years time I bought my 65in LG OLED B7P from Costco during their black Friday sale for $2400....as far as the "our terms" comment goes, I have a really nice set of Klipsch RF-7's and paid $500 for the set. So yeah, I'll take the "cheap" towers every day. Sent from my Pixel 2 XL using Tapatalk Quote Link to comment Share on other sites More sharing options...
vasubandu Posted January 26, 2018 Author Share Posted January 26, 2018 7 hours ago, RoboKlipsch said: avsforum which has a 400 page thread with full time experts in theater installation Thanks for telling me. I will check this out. Quote Link to comment Share on other sites More sharing options...
Khornukopia Posted January 26, 2018 Share Posted January 26, 2018 All the tiny holes in acoustic ceiling tiles are an important aspect of their design, so reading the details about SoundPly micro-perf is interesting. Quote Link to comment Share on other sites More sharing options...
DrWho Posted January 26, 2018 Share Posted January 26, 2018 On 1/23/2018 at 7:42 PM, garyrc said: I have a RSW-15. It does well down to 30Hz according to REW and a calibrated mic, and down to 20 Hz according to Stereophile test tones as measured by a Radio Shack meter. Even with REW, its bass extension (attenuated bass) reaches to 24 Hz. It sounds quite powerful. Its bass is not as clean and tight as that of the Klipschorns it works with. This has made me consider a DIY horn loaded subwoofer. Search the forum, and you will find some info on them. Horn loaded subs need to be quite large. Somewhere on the forum there is one almost ceiling height standing in a corner. Just outta curiosity - have you phase/time-aligned your subwoofer with your khorns? And what xover frequency are you using? I forget the path-length of the khorn bass bin, but you should artificially add distance in your receiver to account for that. If you haven't been doing that, then it should tighten things up quite a bit. Not saying it's as good as the horn loaded bass you're thinking about, but might as well get the most out of our existing systems.... Quote Link to comment Share on other sites More sharing options...
DrWho Posted January 26, 2018 Share Posted January 26, 2018 On 1/24/2018 at 6:41 PM, vasubandu said: If you are really into sound absorption, do me a favor and check out soundply.com. They claim that their "LR Series provides near anechoic-grade sound absorption." The company checks out but I don't have any product yet. You don't want an anechoic room....they exist, and they're horrible for listening to music. Quote Link to comment Share on other sites More sharing options...
Emile Posted January 26, 2018 Share Posted January 26, 2018 On 1/20/2018 at 12:20 PM, The History Kid said: "you need $1,000 solid silver speaker wire." Assume it's $1,000 per foot ... otherwise it's NO GOOD Quote Link to comment Share on other sites More sharing options...
garyrc Posted January 27, 2018 Share Posted January 27, 2018 4 hours ago, DrWho said: Just outta curiosity - have you phase/time-aligned your subwoofer with your khorns? And what xover frequency are you using? I forget the path-length of the khorn bass bin, but you should artificially add distance in your receiver to account for that. If you haven't been doing that, then it should tighten things up quite a bit. Not saying it's as good as the horn loaded bass you're thinking about, but might as well get the most out of our existing systems.... Thanks for the info. I'm using an 80 Hz xover. Audyssey sets the distance for the Khorns at 16 + + feet; they are about 12 feet away in reality. I'm guessing Audyssey looks at the full range of the Khorns, rather than the bass bin alone. Audyssey estimates the distance of the subwoofer at over 20 feet (but I'm told that is primarily because of delay in the sub's circuity). In physical difference, the sub is about the same distance as the Khorns. Quote Link to comment Share on other sites More sharing options...
DrWho Posted February 15, 2018 Share Posted February 15, 2018 On 1/26/2018 at 8:05 PM, garyrc said: Audyssey estimates the distance of the subwoofer at over 20 feet (but I'm told that is primarily because of delay in the sub's circuity). Interesting....who told you that? I thought the RSW-15 had an analog signal path (thus no latency), no? Quote Link to comment Share on other sites More sharing options...
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