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Discussion Starter #82
That's one of the things I plan on testing before actually moving on to the comparison. I plan on testing power levels, and trying to see whether the frequency response will look the same connecting the dots from test tones, as it does from white noise. I have this nagging feeling that it wont, but that's one of the things I'll find out.

My reason for using two was more to make sure the driver stays linear, as depending on the power level we arrive at, 20hz will likely push one driver past linear, which could affect results. But, that is another thing I can test. It may affect results the same in each case, which then wouldn't matter. In the end, I don't think I can fully represent what would happen in a door, which is why I'm more focused on eliminating as many variables as possible, and testing products themselves head to head.

A lot of people on another forum were wanting me to do these tests in an actual door, or with a cut out piece from a floor board, but I wouldn't be able to make sure the products were applied evenly each time, which bugged me, aside from every car being different. I know Erin had thought about doing something with accelerometers and deadening, and I think these are the reasons he never pursued it further. That's why I'm trying to stick to products and application, without applying it towards a certain vehicle.
 

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I'm out of town at the moment, but I might be able to find a few minutes to model the enclosure for you this evening. It shouldn't take me all that long to knock it out since it is the kind of work I do every day. I got that the box would be 1/2" Baltic birch and 13" x 13", but do you know how deep you planned to make it?
 

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There will also be durability testing for heat, using a small toaster oven. I'll use an oven thermometer to get the temps accurate.
Is the goal of this test to show dampening performance after temperature exposure or to see the effects of extended heat exposure on the materials?

What is your target temperature?

You are doing a helluva a service to the community, thanks.
 

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Discussion Starter #85
Dustin, the internal dimensions are 12"x12"x12". The baffles front and back are 3/4" baltic birch, the four sides are 1/2". So, four sides, each side piece is 12"x12.5". I didn't want to do two 12"x13" and two 12"x12" pieces to keep everything equal. Probably wouldn't have had an effect, but you never know. Then the front baffles attach, making the box 13"x13"x13.5" Those front baffles are 13"x13"x3/4", with an 11"x11" cut out.

Astrochex, the oven will be for durability testing. I'd love to do heat related tests of vibration, but I'd need a much bigger oven to get the test size pieces in it. It is something I'd like, just can't afford to do right now. There is a guy at work with plans to build a oven for powder coating, depending on what happens with that, maybe I could do it down the road.

Target temp for the durability testing will be once at 200 degrees, and once at 400. Set for 30 minutes each, and video them, so I can see if and when they fall.
 

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I'm glad to hear that you are doing the temp tests for durability. Your nose might be a guide when it comes to determining failure point. :D

I think that if you were going to do a vibration at temp test series, you would be making a consistent test process a challenge.
 

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Thanks for the figures Chris. Headed back from the NSRA show in Bakersfield now. Probably watching the fights tonight, but I'll see if I can find a few minutes to knock out at least the model enclosure tonight.
 

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Discussion Starter #88
I'm glad to hear that you are doing the temp tests for durability. Your nose might be a guide when it comes to determining failure point. :D

I think that if you were going to do a vibration at temp test series, you would be making a consistent test process a challenge.
That was my worry with it too, is consistency. Without being able to have a chamber to put everything in, including the accelerometer, it would be too hard to keep temps consistent. There is definitely a huge difference in smells though, even at room temps.



Dustin, no worries. What program were you going to use?
 

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I'll probably just do it in Sketchup. It is really quick for knocking out simple models like this. I have some Autodesk software at home as well, but Sketchup is quicker and easier.
 

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Here is a quick model that I threw together to see what the test enclosure will look like. The foreground shows the two pieces that will clamp the metal panels to the enclosure. The background shows the opening for the Hybrid Audio Technologies L6SE. As I have more time, I will model the driver as well as all of the fasteners (including hurricane nuts) and show some exploded views. However UFC 159 starts in just a couple minutes, so this is it for now.

 

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Discussion Starter #91
That's awesome Dustin, thanks. Yep, that's pretty much it. The front baffle will be able to be changed as well, so I can test one vs two speakers, to see what I need to stay within the accelerometers sweet spot.

I picked up the metal as well for the stamps and press plates for applying the deadening. Three x 12"x12"x.25" steel plates. One 4' section of 1.5"x1.5" square tubing to brace the plates, and to stamp the durability test pieces out. One 3' section of 1"x.25" steel strap, for the cutting edges of the press. Hopefully I can weld it all together next weekend and try it out.
 

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If you need someone to weld it up for you, just let me know. My brother could knock it out really quick at his place in Tulare.
 

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Discussion Starter #93
Dustin, that might work best. The guys I have to weld are umm, sketchy at best. Difficult to get the time to get something done, or in the case of one of them, it will take 4 hours to do a 10 minute job. Let me know when you get some time and we can figure it out.

I forgot to update the list, so here it is. I got another sample of GTMat Pro, and 1/3rd roll of peel n seal in. Thanks to those who sent it in.

Ok, this is the list of have in my hands products.

Dynamat xtreme - 1 12"x12"
GTMat Pro 50 Mil - 1 12"x12"
GTMat Ultimate 80 Mil - 1 12"x12"
GTMat 110 Mil - 1 12"x12"
GTMat Onyx - 1 12"x12"
Alphadamp - 1 10"x14"
SDS CLD - 1 6"x10"
Stinger Road Kill Pro - 2 6"x6"
Lightning Audio Deadskin - 1 8"x8"
StP Bomb - 1 sheet
StP Gold - 1 sheet
StP Silver - 1 sheet
StP Vizomat - 1 sheet
Peel N Seal - 1/3 Roll

Things that are on the way or have might soon be on the way

Fatmat
second skin damp pro
edead
possibly some cascade V-2
possibly some knu concepts stuff

That leaves me wanting for the test

cascade vmax
maybe some raamat
 

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I won't be available this weekend as I'm trying to make it up to the Simplicity in Sound open house. Otherwise just shoot me a text and I can coordinate it with my brother. If you don't have my number, just PM me.
 

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Discussion Starter #95
I was really hoping to head up there too, but my dad signed a lease for a shop in Oxnard, and I'll be helping him take the furnaces and evaporator down there Saturday. That should give me this week to get the box made, and next week to get the metal done.
 

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Any update on this yet? Really looking forward to the results! It's one of the reasons I decided to finally actually sign up for these forums!
 

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Crap that reminds me. I never got that Cascade stuff in the mail to you. Sorry, completely slipped my mind. I am also very interested in the results of this with a new ride to fix up now. The new one is a Lexus tho and my feelings are it will require a whole lot less than my previous rattle box. Let me know if you still want me to mail you some and how much you need again. I just looked and I have quite a bit left actually but it is almost 2 years old in my garage so hope that doesn't affect things negatively.

On a side note, I picked up some Alfadamp to try out this weekend. Couldn't wait due to the awesome sale which ended yesterday. Should have it to use in a couple weeks. Parents are going to pick it up in Montana for me and whenever they get up my way I'll have it and I can start getting to work.
 

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Alphadamp was on sale over the weekend?! Ugh...
predope sale; 50 % off pretty much everything. I only grabbed one 20 sqft pack but that should at least do the front doors which will be needed with my Morel 8s pounding them eventually with 340 Mosconi watts on them:cool: I think that pack worked out to about $80 or so and shipping was very reasonable - they sure have changed that for us Canadians - thanks alot Ant:D even if I chose to get it sent to Montana this time anyways. I also grabbed 100 ft of 16 ga and some 16 ga quick disconnects as well for the hell of it. It will be nice to have three runs of different looking wires on each side for the 3 way front. I probably have enough good wire already but this will be the third car these have been in and there are several areas on each line that have been soldered which I am sure affects the sq in some way. If nothing it will be easy to figure out which line is for what speaker:D
 

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Discussion Starter #100
Sorry for the lack of updates, had a parent in the hospital. I did get to box built, and got a power supply for the amp and source unit for the speaker I'm using the excite the panel. I'll be soldering on the new cap's to the accelerometer board later this week, and then starting to test things out and get a feel for the measurements I'll be getting. I also got the toaster oven for heat testing, so I'll move forward with that this weekend. I fired off an email to all companies for whom I have product from, asking for MSDS sheets, product specs (some aren't publicized), and the best way to remove in case the need arises.

After talking with my dad, I'll be skipping the RTA for accelerometer date acquisition. I'll be using the o-scope and manually importing the data over. After talking with my dad, this is the method which he felt would produce the most accurate, repeatable measurements, and avoids relying on Fourier transform math, which he believes adds another variable. In his explanation, he showed me the model of a computer generated sound, one of them made with Fourier transform math, and one made with FEA modeling. The sound was supposed to be that of air blowing through an aluminum tube. The FEA generated sound sounded very life like, almost real. It also took 6 hours for his computer to go through all the calculations. The Fourier transform sound did not sound right. If I had to compare, it would be the sound of the voice programs, where they sound almost metallic. It was however, much simpler and quicker to put together (probably why this is as far as most people venture into it).

That said, if anyone is good with Labview Signal Express, and wouldn't mind walking me through it, that might be able to save some time. Its not a very intuitive program, and my dad never bothered to learn since National Instruments doesn't document anything in it very well (and expects you to pay for their training). My dad is working on a program in C, to automate the process of taking measurements, but it probably wont be ready by the time I'm wanting to start.


James, ya if you can send it that would be great. I was looking on parts-express for the price of buying some, and they want around $60 minimum, as you have to buy a good amount of it.
 
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