When I did this on my cabinets, the Decidamp wasn't available (not invented yet) so I did the constraining layer with primer on the wood and silicon caulking compound which seemed to work well enough.
I just built 48x14x11" enclosures out of 3/4 MDF for my TangBand W8-2145 full range speakers. LOTS of screws and adhesive, but no bracing otherwise. The results have been incredible. Huge punchy and wide bass with all the great mid and highs to go with it. I was worried about bracing, but in this experiment, just didn't seem necessary. MDF is a nightmare tho. The dust is horrid, very heavy and frankly difficult to work with. That said, I've never had luck with ply cabs. YMMV.
MDF dust messes with my lungs for days afterward, unless I take steps to prevent it.
MDF dust may be cancerous so that should be a consideration. Cheap plywood from Home Depot may cause some resonance at the upper midrange but can be managed with proper bracing. The most practical solution probably gluing together different types of board into about 1in. thick or more for the front baffle and probably 3/4in. for the side and rear panels.
A plywood panel will have some natural resonance at some discrete frequencies if not well treated. Ultimately, you want to distribute the energy evenly to a broad band of frequencies and NOT concentrate to a few discrete frequency bands. There are different solutions but at the end, that's what you want to do.
A plywood panel will have some natural resonance at some discrete frequencies if not well treated. Ultimately, you want to distribute the energy evenly to a broad band of frequencies and NOT concentrate to a few discrete frequency bands. There are different solutions but at the end, that's what you want to do.
Certainly not a full indepth study but a very good indication of comparison to non-CLD effects.
Yep, either way will work. I just wanted to avoid making sheets of CLD sheets than have to cut it.
Me too Allen. I have a very powerful dust collection system and a professional breather but still that crap shows up for months anyway.
I decided last night, after reading through all these great comments, to use good 1/2" plywood, a layer of Decidamp, then another sheet of 1/2" plywood.
So 1" of CLD plywood in the end. Don't know about bracing yet. I have to think on that more.
If the woofer, or subwoofer, is big, then you can add a table inside.
Humble Homemade Hifi - Twenty Five
Humble Homemade Hifi - Twenty Five
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Or, as Tony Gee, you can build ALL with 1" plywood with woofer reinforments. And the internal walls put viscoelastic, in addition to between the front and the reinforcement. Less work.
[PDF] http://www.humblehomemadehifi.com/download/Humble%20Homemade%20Hifi_Calpamos.pdf
[PDF] http://www.humblehomemadehifi.com/download/Humble%20Homemade%20Hifi_Calpamos.pdf
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Short answer: Yes they are.
The designers may crank out a near perfect driver/cabinet/crossover combination but then the needs of manufacturing take over. Assembly order dictates changes in wiring, machining and fastening. Available parts lead to compromises in crossover construction, ports and drivers. Costs play into choices about materials and fasteners.
In the end, virtually everything where more than one is built has compromises.
It might not make much difference but an inner layer of MDF which is much more structurally bonded than plywood makes more sense to me. I know the stuff is a real bear to work with but in the long run it might be better.
The thumbnail is me putting finishing touches on my boxes from 1979... I apologize for the image quality but it's the sole remaining picture of that build. If you look closely you can see the layered construction. That was a sealed box, very air tight, with a 12 inch woofer, 2 x 4 inch mids and 2 x 1" dome tweeters, a 3 way 2nd order crossover, all Phillips Deforest line products.
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Can you provide a link to a real research paper demonstrating this? I do realize you included "may" and I can find this claim easily on the internet but only on forums with the same amount of scientific basis as diyaudio.
Similarly, when I googled about MDF, I found "Wood dust, especially from hardwood, causes nasal and sinus cancer in woodworkers. Some of the species known to cause cancer include the hardwoods oak, mahogany, beech, walnut, birch, elm and ash. As with formaldehyde, these cancers take years to develop and generally require significant, ongoing exposure for a long period of time."
I have a dust collector and wear a mask using MDF or wood.
Those speakers must have furnished some flare flapping moments Douglas!
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I've found this Finnish research paper published online in 2012:
Occupational exposure to wood dust and formaldehyde and risk of nasal, nasopharyngeal, and lung cancer among Finnish men
I have been looking at prices for those viscoelastic products and they are very expensive, like years ago.
Luckily I thought about going to a construction warehouse chain. Isolana, with a near shop in Tarragona province (La Canonja).
[Spanish, PDF] https://isolana.es/es/documentacion/tarifa2018/aislamientos-2018.pdf
[Spanish, PDF] https://isolana.es/es/documentacion/tarifa2019/Generica/2.0/TarifaGenerica2019.pdf
TECSOUND(R) SY
[English, PDF] http://www.texsa.com/pdfproducto/en/pl39/productos/id63/tecsound-sy.pdf
I have a Big roll of Tecsound SY 70.
Luckily I thought about going to a construction warehouse chain. Isolana, with a near shop in Tarragona province (La Canonja).
[Spanish, PDF] https://isolana.es/es/documentacion/tarifa2018/aislamientos-2018.pdf
[Spanish, PDF] https://isolana.es/es/documentacion/tarifa2019/Generica/2.0/TarifaGenerica2019.pdf
TECSOUND(R) SY
[English, PDF] http://www.texsa.com/pdfproducto/en/pl39/productos/id63/tecsound-sy.pdf
I have a Big roll of Tecsound SY 70.
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