My next project

[NickH]

Ok thats what I thought it was. We are on the same page. Thats why I was going to try the asphalt roof cement.

Heres a link.

http://www.homedepot.com/h_d1/N-5yc1...&storeId=10051

Just think this would be easier to put on in the tight space.


Has a thick consistency. So I would put it on with a putty knife. Works on vertical surfaces. Only 14 bucks for a can so I figured I might as well give it a try.

Tar panels, ranging from 2mm and up are used in the automotive industry to keep flat sheet panels from vibrating by adding inertia/mass. Otherwise the car would literally be a bell. You can also find variations in the automotive sound system world where people apply massive amount of such panels to keep the car from resonating. Most often, those panels have a peel-off/stick-on back. Therefore they are very easy to use.



Dynamat is the original supplier. But they are very expensive. You can find similar products for much cheaper.

http://www.b-quiet.com/extreme.html



For one tenth the price, you can go to your local Lowes renovation center and get roofing material. ;-)

http://www.scroungers.net/t475-cheap...ive-to-dynamat



You can find thicker stuff from other sources. The thicker, the better. I also suspect that every single panel in your A7 would benefit from a sheet or two of such sound deadening material to keep them from vibrating. Old wood, thin wood, dry wood will easily resonate.

[NickH]

Nothing much to report on the progress. Im filling in defects at the moment. Im working on one cabinet at a time now. Otherwise it seems like im not getting anything done.

I did decided Im going to put 3/4" baltic birch ply on the sides and bottom of the cabinets. It going to make them heavy but I have most of the ply on hand so I only have to buy a little bit.

Ill post some pictures soon.


Nick

[NickH]

Well I glued some 3/4" birch ply on the sides of one cabinet this weekend. Went well. There getting heavy, LOL. I also got some asphalt roof flashing cement to try for dampening the horn flares. I put the stuff on a piece of 1/4" plywood. Im surprised that the stuff doent really have much of an odor. It takes a long time to cure but so far it works prtty well. Looks like goose poop though, . But I can knock on the wood pretty hard and all I get is a thud. So it looks like it

Today I started filling in the gaps on the front of the cabinet. The original plywoods corners are rounded over from years of road use. So theres a little gap on the periphery.



Here are some photos of the progress. The dampening material I tried. And the experiment.

Not in any particular order.

Nick

[intercity125]

Hi Heather,

I'm not putting it on the inside of the horn. Its the outside the horn bells inside the cabinet. But I'm going to do some experimenting first before I use it on the horns. Silicone is a really good idea. But I don't think it would work to well here. Its a tight squeeze getting in there. I don't even I can't get a brush in there.

The reason I'm thinking about the asphalt cement is asphalt seem to do very good at deadening vibrations. That's what things like dynamat is made of. I would use dynamat but its just so expensive.

My experimental method isn't very complex. Just coat some 1/4" plywood with it and tap on it with a hammer to see if it sounds dead.

But that being said I think I might try out some rtv silicone just to see how it performs. Just might be quite tricky applying it to the inside of the horn cavities.

Nick

Hi Nick,

Awesome project! I look forward to seeing the final results. In fact, I will be starting yet another one myself... a pair of bass enclosures for the 416 driver. I am going to model them after the Altec 620's, but with some added refinements. Anyway, since there was some talk about damping, I thought I would chime in. I use a product from Dupli-Color called "Professional Undercoat and Sound Eliminator." It is amazing stuff, and unlike all the other rubberized sprays on the market, this one does not leave a shiny, smooth surface. Rather it has more of a bituminous texture that really deadens sound. I use it inside of all my speaker cabinets/projects. Most recently, a pair of Klipsch Belles that I refurbished. The only place I have found to carry it around here is Pep Boys. They keep it next to all the paints and auto body products. Just something to consider down the road.

Willy

[NickH]

Hi Willy,

I bet you a dollar that can is filled with basically the same thing as this cement. Asphalt. And low and behold, it is. Heres a link to the msds.
http://www.paintdocs.com/webmsds/web...pe=MSDS&lang=2

The reason Im drawn to the cement is the price. Most products that are for dampening carry a high price tage. This stuff can be had for 15 bucks a gallon.

This is what Im trying.
http://www.karnakcorp.com/19Flashing.aspx

Hi Nick,

Awesome project! I look forward to seeing the final results. In fact, I will be starting yet another one myself... a pair of bass enclosures for the 416 driver. I am going to model them after the Altec 620's, but with some added refinements. Anyway, since there was some talk about damping, I thought I would chime in. I use a product from Dupli-Color called "Professional Undercoat and Sound Eliminator." It is amazing stuff, and unlike all the other rubberized sprays on the market, this one does not leave a shiny, smooth surface. Rather it has more of a bituminous texture that really deadens sound. I use it inside of all my speaker cabinets/projects. Most recently, a pair of Klipsch Belles that I refurbished. The only place I have found to carry it around here is Pep Boys. They keep it next to all the paints and auto body products. Just something to consider down the road.

Willy

[intercity125]

Hi Willy,

This is what Im trying.
http://www.karnakcorp.com/19Flashing.aspx

The Karnak looks like great stuff, too. Also, I like that you can get it in an industrial size can. It will definitely go a lot further than the Dupli-Color spray cans I am using now. Thanks for turning me on to it. BTW, are you brushing it on, or can it be applied with a spray applicator?

[NickH]

The first test I used the caulk tube. But that was just because I didnt want to buy a gallon can and didnt know if it was going to work or not. The caulk gun tube is handy but it cost more. I was going to try and put it on with a putty knife at first. But I need to do more experimenting to find the best way.

Nick

The Karnak looks like great stuff, too. Also, I like that you can get it in an industrial size can. It will definitely go a lot further than the Dupli-Color spray cans I am using now. Thanks for turning me on to it. BTW, are you brushing it on, or can it be applied with a spray applicator?

[intercity125]

The first test I used the caulk tube. But that was just because I didnt want to buy a gallon can and didnt know if it was going to work or not. The caulk gun tube is handy but it cost more. I was going to try and put it on with a putty knife at first. But I need to do more experimenting to find the best way.

Nick

I suppose one just has to trowel (or putty knife) it on as smoothly and evenly as possible. Alternatively, I see a few places on-line where you can get fillable caulk tubes. That may make it easier to apply, then all you have to so it smooth it to effect.

[NickH]

I might have to check those out. The one thing I do know about this stuf is it take awhile to cure. Over 24 hours. I havent tested it's ability to flow when effected by gravity yet. Just put it on a horizontal surface, at the moment.

I suppose one just has to trowel (or putty knife) it on as smoothly and evenly as possible. Alternatively, I see a few places on-line where you can get fillable caulk tubes. That may make it easier to apply, then all you have to so it smooth it to effect.

[intercity125]

Hey Nick,

Do you have the crossovers for this project yet? Just curious. If so, what do you have? If not, do you know what you are going to use?

Willy

[NickH]

Hi Willy,

I was planning on going active. Using a minidsp. If you need inspiration there are plenty of altec and jbl crossovers that you could clone.

Hey Nick,

Do you have the crossovers for this project yet? Just curious. If so, what do you have? If not, do you know what you are going to use?

Willy

[intercity125]

I see. Well, it seems to be the way things are going, these days. I've yet to venture down that road; however, I can see where going active makes perfect sense. A good friend of mine from Universal City has a wonderful pair of Emerald Physic 2.3's that use an active crossover, and the slopes and crosses are literally endless. Want to change the tone, push a button. Want to shift the soundstage, push a button. It's like auditioning a new pair of loudspeakers with every change. Great stuff, really. I may have to go that route after I refurb my KEF 105's.

[NickH]

The in the realm of rf engineers they alway say" why do it high level when you can do it in low level". Seems to make since here too. Just mean you need multiple amps. But in a world where you can get class d amp borads that sound quite good for around 100 bucks and produce anywhere from 8 watts per channel up to 300 watts per channel. Works for me. Just need to supply the power supply.
Nick

I see. Well, it seems to be the way things are going, these days. I've yet to venture down that road; however, I can see where going active makes perfect sense. A good friend of mine from Universal City has a wonderful pair of Emerald Physic 2.3's that use an active crossover, and the slopes and crosses are literally endless. Want to change the tone, push a button. Want to shift the soundstage, push a button. It's like auditioning a new pair of loudspeakers with every change. Great stuff, really. I may have to go that route after I refurb my KEF 105's.

[NickH]

Almost done with the first box. I wonder how these would sound with a sealed box. Oddy enough they sim quite well in win isd.

[sbjacob]

Almost done with the first box. I wonder how these would sound with a sealed box. Oddy enough they sim quite well in win isd.

Those are looking very cool I bet they will put out some nice LF with all the added cabinet support.