DIY Speakers and Acoustic Panels
- Thread starter DM60
- Start date
mjbphotos
Moderator
I work with gases. The only way to 'flush' the cabinet with helium would be to have an exit port and would take overpressurizing, pushing air out multiple times. Helium atoms are small - they will diffuse out faster than air, so his numbers really don't mean much in that part of the experiment. But it was interesting that all the different speaker designs made very little difference.
The materials analysis of the various types was more interesting. Never heard of using TP! Not surprising results using rockwool, and interesting that adding foam to roxul was not good. I'd like to see him do it with OC703/705.
Keep this youtube bookmarked to share the next time someone here suggests egg cartons!
The materials analysis of the various types was more interesting. Never heard of using TP! Not surprising results using rockwool, and interesting that adding foam to roxul was not good. I'd like to see him do it with OC703/705.
Keep this youtube bookmarked to share the next time someone here suggests egg cartons!
Folkcafe
Active member
I was recently reading about how the Navy built an anechoic chamber with no absorptive materials at all. It is constructed entirely of stainless steel wedges. The biggest flaw I see in this video is it completely ignores the biggest challenge studios have with treatment, bass. Low bass especially.
Absorptive materials effectiveness is factored on a number of things. The above suggestion about 703 & 705 would be illustrative of one factor. As the thickness of these materials increases, you get to a point where it becomes reflective vs absorptive. After 4 inches this becomes the case with rigid fiberglass and light density pink fiberglass outperforms it at lower frequencies. The rating you need to be aware of is gas flow resistivity. If you know this density spec, you can enter it into this calculator and compare performance. acousticmodeling.com
So for instance OC EchoTouch R19 has a rating of 2900 and OC 703 is 18000. Plug those numbers into the calculator and steadily increase the thickness without an air gap and watch the graph change as it gets thicker.
Note for clarity, should read lighter density insulation which would include lower density semi rigid first and as you go thicker, light density pink fluffy stuff. It is a point of diminishing returns at thickness and materials for use has to be considered in the equation.
Absorptive materials effectiveness is factored on a number of things. The above suggestion about 703 & 705 would be illustrative of one factor. As the thickness of these materials increases, you get to a point where it becomes reflective vs absorptive. After 4 inches this becomes the case with rigid fiberglass and light density pink fiberglass outperforms it at lower frequencies. The rating you need to be aware of is gas flow resistivity. If you know this density spec, you can enter it into this calculator and compare performance. acousticmodeling.com
So for instance OC EchoTouch R19 has a rating of 2900 and OC 703 is 18000. Plug those numbers into the calculator and steadily increase the thickness without an air gap and watch the graph change as it gets thicker.
Note for clarity, should read lighter density insulation which would include lower density semi rigid first and as you go thicker, light density pink fluffy stuff. It is a point of diminishing returns at thickness and materials for use has to be considered in the equation.
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DM60
Well-known member
Or foam panels!
I posted because it supports, long winded, everything that is stated on the board.
Cool I was just thinking about how to make these the other day. Funny enough I was considering using the same rockwool! I actually use it at work all the time and thought it would probably be a good material for the Showbox jiofi.local.html tplinklogin job.
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farhanahmed639
New member
I would suggest, certified acoustic curtains from Saaria Inc. They have the best reviews out there I've read them personally.
rob aylestone
Moderator
I’ve read Stephen king, doesn’t mean they’re true. What we are missing here is detail and purpose. Those acoustic curtains appear to be drapes with heavy linings, primarily with prettiness the selling feature. They don’t even seem to offer specs?
if you go to well known and respected studios, and I’ll use abbey road, air lyndhurst and strawberry studios Manchester as examples of studios where well known music has been recorded and I have physically been in them, as examples. They are very different to just stand in. Air is like a nice clean small chapel. If you close your eyes you know it’s large and has lots of surfaces. Abbey Rd is biggish but sounds like a well controlled gymnasium where you can hear the reflections and yet it’s nice to be in as it’s somehow smaller than it really is? Strawberry, the original Strawberry was horrible. So much treatment to fix the boxy space that all the life was sucked out. No point clapping your hands, the room hoovered the reflections up. It was a long time ago, and I was very young but I remember everyone waiting for somebody to call a break so everyone could go outside for some real air.
what I’m trying to say is we are applying specs intended for business noise control and keeping adjoining homes isolated to music. If we have very frequency specific issues, then it’s not the stuffing of a trap we should talk about at all, but the type of trap, and if we actually need to remove this energy or disperse it somewhere else? Removal is not our only tool, but we talk as if it is, like builders. We have 90 degree corners causing a problem, so fill in the corner with a 45 degree panel and change the room sound drastically. it probably means another ‘problem’ appears somewhere else, but we are not doing it as a business, it’s for many a hobby. Science dictates things that often cost a fortune to do and sometimes still sound horrible. The uk magazine sound on sound have been doing home studio fixes for years, and a duvet on a couple of boom stands is a usual quick test solution because they can move it around an test what their ears suggest. Once the cure is solid, then they source proper product, but often the spaces are living rooms or bedrooms and they simply suggest leaving the stands in a cupboard and getting them out when needed as the real acoustic treatment takes up valuable living space. Those aesthetically designed ‘acoustic curtains‘ might actually be enough. I’ve read the books, and in the best, like rod gervaise’s there is an undercurrent of don’t go too far and diminishing returns warnings. You want to remove what spoils your work. If you have a huge accidental resonance at 63Hz that makes a piano or bass seem to have one crazy note, that needs sorting. If the result is a gentle rise and fall you can live with that happily. If you have a huge sponge at 2.5K that will hurt voices, so find it and fix it. Too much absorption to get a flatter line is tiring to play in and depressing. It messes with your head. At the end of my studio there are some flutters from the close parallel walls and I play keys in that bit and pure sounds appear kind of phasey? Both faces doing the reflecting now have those 50mm 300x300 foam tiles on. Above 5k or so they’ve got rid of that phased reflective sound. They allow the bass to bounce unrestricted but that isnt annoying.
I have failed to interpret specs in any musical way. They’re good clues, but nothing has ever predicted the sound of any of my studios in more than a rough way. I simply don’t understand folk who spend their money before using their ears.
if you go to well known and respected studios, and I’ll use abbey road, air lyndhurst and strawberry studios Manchester as examples of studios where well known music has been recorded and I have physically been in them, as examples. They are very different to just stand in. Air is like a nice clean small chapel. If you close your eyes you know it’s large and has lots of surfaces. Abbey Rd is biggish but sounds like a well controlled gymnasium where you can hear the reflections and yet it’s nice to be in as it’s somehow smaller than it really is? Strawberry, the original Strawberry was horrible. So much treatment to fix the boxy space that all the life was sucked out. No point clapping your hands, the room hoovered the reflections up. It was a long time ago, and I was very young but I remember everyone waiting for somebody to call a break so everyone could go outside for some real air.
what I’m trying to say is we are applying specs intended for business noise control and keeping adjoining homes isolated to music. If we have very frequency specific issues, then it’s not the stuffing of a trap we should talk about at all, but the type of trap, and if we actually need to remove this energy or disperse it somewhere else? Removal is not our only tool, but we talk as if it is, like builders. We have 90 degree corners causing a problem, so fill in the corner with a 45 degree panel and change the room sound drastically. it probably means another ‘problem’ appears somewhere else, but we are not doing it as a business, it’s for many a hobby. Science dictates things that often cost a fortune to do and sometimes still sound horrible. The uk magazine sound on sound have been doing home studio fixes for years, and a duvet on a couple of boom stands is a usual quick test solution because they can move it around an test what their ears suggest. Once the cure is solid, then they source proper product, but often the spaces are living rooms or bedrooms and they simply suggest leaving the stands in a cupboard and getting them out when needed as the real acoustic treatment takes up valuable living space. Those aesthetically designed ‘acoustic curtains‘ might actually be enough. I’ve read the books, and in the best, like rod gervaise’s there is an undercurrent of don’t go too far and diminishing returns warnings. You want to remove what spoils your work. If you have a huge accidental resonance at 63Hz that makes a piano or bass seem to have one crazy note, that needs sorting. If the result is a gentle rise and fall you can live with that happily. If you have a huge sponge at 2.5K that will hurt voices, so find it and fix it. Too much absorption to get a flatter line is tiring to play in and depressing. It messes with your head. At the end of my studio there are some flutters from the close parallel walls and I play keys in that bit and pure sounds appear kind of phasey? Both faces doing the reflecting now have those 50mm 300x300 foam tiles on. Above 5k or so they’ve got rid of that phased reflective sound. They allow the bass to bounce unrestricted but that isnt annoying.
I have failed to interpret specs in any musical way. They’re good clues, but nothing has ever predicted the sound of any of my studios in more than a rough way. I simply don’t understand folk who spend their money before using their ears.