[walkern]

I built a pair of RAW Acoustics RA-8 speakers several years ago (still have them and love them), and per Al's recommendation, the cabinets (tall line source design with Danny's drivers and crossover design) are first lined with soft linoleum floor tile and then a layer of cheap mattress pad foam stapled over it.  The cabinets are over 5 feet tall, yet they are very effectively damped and non resonant using this approach and the total cost was about $30.  They are very well braced to begin with, so I believe that also helps them remain quite 'dead'.  It is quite easy to do.  The only challenge was that the floor tile pieces (which are really easy to cut to fit) don't stick (using the peel and stick adhesive on them) as well as one would like.  So stick on each tile piece, and then staple the foam over it immediately thereafter and you wont be stuck going back and re-attaching falling pieces of tile.

Neil

[dvenardos]

So Stephen are you an expert yet, any ideas on what you are going to do?

Here are the industrial floor tiles Danny was talking about.
http://www.homedepot.com/Flooring-Vinyl-Resilient-Flooring-Vinyl-Tile/h_d1/N-5yc1vZ1xhcZaq27Z1z11ijz/R-100183098/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

Let me ask this. None of the sound absorption material that I have seen is rated below 120hz, so if the application is for a subwoofer (either boxed or OB) what is the point of the open cell foam layer? 

edit: from another thread.
What about this stuff instead of the floor tile?
http://www.edesignaudio.com/product_info.php?cPath=1_24&products_id=786

Peel and stick .15 inch thick tiles. More expensive, but might be worth the convenience.
http://www.homedepot.com/Flooring-Vinyl-Resilient-Flooring-Vinyl-Tile/h_d1/N-5yc1vZ1xhcZaq27/R-100593151/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

[django11]

As usual I'm more confused instead of less .

I received a flyer today with 15 ply 1 inch Russian birch plywood.  That is interesting.

I'm still debating as to whether I get the N2s or N3s (for near field?).    If I get the 2s I'll probably just spring for the No Rez.

I am tempted to try the peel and stick tiles.  You can get them for fifty cents a foot around here.  The wife works in the clothing industry so the foam shouldn't be a big challenge.

When I think of what was in my x-ls speakers, I don't think I can do worse than that.  And I can always upgrade to the No Rez later...

[dvenardos]

No one? 

Let me ask this. None of the sound absorption material that I have seen is rated below 120hz, so if the application is for a subwoofer (either boxed or OB) what is the point of the open cell foam layer? 

[Danny Richie]

No one? 

In that regard it really doesn't matter as the wavelengths in those ranges are so long that you can't propagate a single wavelength in the box. You are just creating changes in air pressure.

The damping material still slows the flow of air movement in the box and does add in tuning. It also can absorb any high frequency overtones that passes through the crossover at low level. This can vary though from very little to zero.

[dvenardos]

Thanks Danny. 

[django11]

I found some very interesting stuff here: http://www.silcom.com/~aludwig/Loudspeaker_construction.html  Especially the section titled "Panel Vibration Damping Experiments"

Here is the gent's background http://www.silcom.com/~aludwig/aboutthe.htm

I think I am going to try a "constrained layer" talked about in the above section and illustrated here http://www.silcom.com/~aludwig/images/sandwhc.gif

BTW, as I have stated, I like No Rez but getting the stuff to Canada makes it quite pricey.  I have everything handy to do the constrained layer at no cost...

[dvenardos]

Finally got a chance to read the full article, good stuff. The only problem is that he didn't adhere the damping layers so that really throws off the comparisons.

[rajacat]

I'm not sure if this is exactly the same as No Rez but it looks very similar.



http://shop3.mailordercentral.com/supersoundproofing/prodinfo.asp?number=09-42727

-Roy

[dvenardos]

Doesn't look like that has a damping layer.

[S Clark]

I'm not sure if this is exactly the same as No Rez but it looks very similar.



http://shop3.mailordercentral.com/supersoundproofing/prodinfo.asp?number=09-42727

-Roy

This stuff isn't open cell, therefore it will be reflective and will decrease the internal volume. 

[dvenardos]

I went in to Home Depot to pick up some of the commercial vinyl tile to use as a damping layer in some of my projects and I found this tile that is just shy of 1/8" at .12" and is more expensive, but is self-adhesive. It also looks nice. I picked up a box.
http://www.homedepot.com/Flooring-Vinyl-Resilient-Flooring-Vinyl-Tile/TrafficMaster/h_d1/N-5yc1vZ1xhcZaq27Z5bx/R-202191236/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

[django11]

Just to update this thread I decided to try a constrained layer which goes like this: three thicknesses of ice and water shield plus 1/4 Masonite  adhered to the ice and water shield with Blue Seal (a spreadable waterproof rubber membrane) and mechanical fasteners .   After that I just tightly fitted about an inch of rock wool and then loosely filled the rest with fiberglass.
BTW I had all these materials laying around as leftovers from jobs.  So total cost is:0$.

I can only evaluate the result subjectively or with the rap test.  Subjectively I like the result a lot.  The rap test reveals a very sturdy and quiet box.  If I rap on the 1 1/8 thick oak stair tread which is nearby and then on the speaker the sound from the rap on the stair is much, much louder.  The sound from my speaker is actually very similar in tone and volume to the sound I get when rapping on the ceramic covered concrete floor.  Like a rock...

[HT cOz]

Just to update this thread I decided to try a constrained layer which goes like this: three thicknesses of ice and water shield plus 1/4 Masonite  adhered to the ice and water shield with Blue Seal (a spreadable waterproof rubber membrane) and mechanical fasteners .   After that I just tightly fitted about an inch of rock wool and then loosely filled the rest with fiberglass.
BTW I had all these materials laying around as leftovers from jobs.  So total cost is:0$.

I can only evaluate the result subjectively or with the rap test.  Subjectively I like the result a lot.  The rap test reveals a very sturdy and quiet box.  If I rap on the 1 1/8 thick oak stair tread which is nearby and then on the speaker the sound from the rap on the stair is much, much louder.  The sound from my speaker is actually very similar in tone and volume to the sound I get when rapping on the ceramic covered concrete floor.  Like a rock...

That sounds like it would be bullet proof! 

[se-riously]

Just wanted to point out my experience with the Home Depot industrial floor tile listed in post #51.

First off, does this tile combined with 1" thick open cell foam work as a reasonable low-cost substitute for No Rez?  Hell yes!     I just lined the interior of a pair of AV123 ELT 525M monitors and compared them back-to-back to a bone stock pair.  I can easily tell that the bass was tighter, punchier, and far cleaner than stock.  I wasn't really surprised when I opened up the cabinet and discovered that the speakers were constructed using 0.5" thick MDF - good quality for the price of the speakers though and a beautiful veneer.

Danny was spot on when he said that No Rez is a good value if you don't have the time and effort for the DIY option.  The floor tile is very easy to "cut" (by using a blade and making a score line and then bending the tile along the line until it breaks).  But it is very inflexible, meaning that I would recommend this material for flat surfaces only.  Curved cabinets?  Forget it and just use the real thing.  I also recommend that after you size your piece properly, cut in into smaller sections as needed so that it easily fits through the holes in your baffles without having to bend it.

Also, the self-adhesive is weak (it's designed to take advantage of gravity and rest on a floor remember?) and using contact cement is a must for proper adhesion to the cabinet.  I used a non-flammable contact cement (water based) so that it doesn't stink up the house.

[Poultrygeist]

My buddy used Lowes' Peel and Stick to dampen the interior of his truck. Peel and Stick is a roofing sealer and is very popular with car audio guys who use it instead of the expensive Dynamat.

[Early B.]

Old thread, but new question...

Will adding mass to the cabinet perform essentially the same function as No Rez? I'm thinking of installing granite "accents" to the outside of my subwoofer cabinets which will significantly increase the weight and I assume will reduce vibrations, but I don't want to be presumptuous, hence the question. Thanks.