[FullRangeMan]

I wouldn't mind investing in gathering a bunch of materials, if it was clear what the key mechanical properties of the materials were WRT bending waves.  Then it's a case of gathering a range and seeing what correlates with the "best" sound.

According Zygadr in the past pages, the best material until now is GatorFoam and the best exciter is the Dayton, what I believe.
But if someone can afford to test a CarbonFiber plate I thanks in advance.

[Speedskater]

Back in the mid 1990'es at a boat show I received a sample sailboat batten. It was carbon fiber, Styrofoam, carbon fiber. It was about the size of a doctors tongue depressor and weighed almost nothing. It was stiffer than a same size piece of steel.  So the technology has been around for over 15 years.

[Donka]

Well, my sheets of Gator Board arrived and the exciters arrive today, however I have yet to locate a in-state supplier of the 10mil VHB listed by Zygadar, so that I can get it before the weekend.

So my question is should I go with 3M 4926 which is a 15mil conformable foam VHB, or will the foam have a negative dampening factor?
 
Go the route Tymphany suggests and use CA glue with activator, which I already have a comparable gel to the one they list.

Or wait until next week and order the 3M F9473PC originally listed by Zygadar, which is a single 10mil thick clear acrylic adhesive.

Has anybody tried the super glue method?  I wonder if it would allow for easier removal without destroying the exciter or gatorboard since a lateral sheer force should break the 8 point bond.

Your thoughts...

[usp1]

use fishing line attached to the four corners of the panel(tied through small holes drilled in the corners?) and then tie these to the dowel posts with a few inches of line separating the panel from the posts.
 The ends of the posts can be grooved to stop the line from moving about.

This is what I was suggesting earlier. The frame could be made like a door frame (except closed at the bottom) 4 pieces of fishing line could connect the four corners of the gator foam to the frame. depending on how tightly you stretch the fishing line you would end up tensioning the panel. From afar the gator foam would be appear to be suspended in thin air!

[bobloblob]

As to the sheer force of the super glue, it will give relatively easily when knocked hard from the side, but it may be stronger than the top laminate of the Gatorfoam, and it may soak into the top laminate of the Gatorfoam a bit.  In either case, it would pull off some of the laminate when hit.  I would experiment first.  An uncle who worked for NASA used to use it to lift large blocks of steel by attaching a small plate with an eye on it, so that they could be lifted with a crane,  After it was moved, he said he would hit the plate from the side with a large hammer and break the bond.  Here, you are dealing with something other than blocks of steel, so beware.

Many contact adhesives and tapes become more flexible and lose some of their grip when heated.  Often a hair dryer is enough to get them to release with only a little steady pull.  I use this to get old tape and labels off.  Also, many adhesives are somewhat soluble in naptha, mineral spirits, or mineral oil.  Some of this spread sround the site and reapplied a couple of times may loosen even the adhesive zygadr uses, while not damaging the Gatorfoam, though it may slightly discolor the area, but maybe only temporarily.  On black it shouldn't be too visible, and it would only be on the back anyway.  The combination of heat and solvent should work even better, but have ventilation.

[optic]

For those who like more info on the more ideal panel here is a link:

http://www.google.com/patents?id=nW-JAAAAEBAJ&printsec=abstract&zoom=4&source=gbs_overview_r&cad=0#v=onepage&q=&f=false

Based on the info in this patent. Gatorfoam is damm close to being ideal. I use gatorfoam on my panels. They sound great. The only problem i have is they are so large. I need a bigger room!

Cheers

[HenryPercy]

I just received some exciters from Dayton Audio.  They came with a technical instruction sheet from NHT which recommends placement at coordinates such as 4/9x 3/7y.  Does anyone know the total size of the grid?

[HenryPercy]

On second thought, could they mean 4/9ths of the width and 3/7ths of the height?  Sounds unlikely to me, but maybe that's it.

[HenryPercy]

Zygadr -  Do I recall correctly that you removed the entire plastic housing from the exciters?  If so, how did you keep from damaging the exciter?

Thanks.

- Henry

[FullRangeMan]

On second thought, could they mean 4/9ths of the width and 3/7ths of the height?  Sounds unlikely to me, but maybe that's it.

This position data are intended for when you are using just one exciter.   Why they always think people will use just one exciter with just 6W!!

[HenryPercy]

On second thought, could they mean 4/9ths of the width and 3/7ths of the height?  Sounds unlikely to me, but maybe that's it.

This position data are intended for when you are using just one exciter.   Why they always think people will use just one exciter with just 6W!!

The instructions indicate positions for 1,2,3 and 4 exciters on a panel.  Do you know how to interpret them?

[FullRangeMan]

The instructions indicate positions for 1,2,3 and 4 exciters on a panel.  Do you know how to interpret them?

I think yes, this coordinates are fractions of the width and height of the panel.   They not info the width and height of the panel, because this is for you choose.
Like all exciters will be in the middle vertical of the panel, the first thing you will calc is the distance from the first exciter and then just go ahead, because all exciters are the same distance from each other.
Dayton do not know all exciters must stay in the vertical middle of the panel like the Podium speakers, for this they info two coordinates on this paper.   Do you get ?
What is the size of your panel??
How many exciters you will use in each panel??

[HenryPercy]

The instructions indicate positions for 1,2,3 and 4 exciters on a panel.  Do you know how to interpret them?

I think yes, this coordinates are fractions of the width and height of the panel.   They not info the width and height of the panel, because this is for you choose.
Like all exciters will be in the middle vertical of the panel, the first thing you will calc is the distance from the first exciter and then just go ahead, because all exciters are the same distance from each other.
Dayton do not know all exciters must stay in the vertical middle of the panel like the Podium speakers, for this they info two coordinates on this paper.   Do you get ?
What is the size of your panel??
How many exciters you will use in each panel??

I have two panels of Gatorfoam, each 4' x 8'.  I plan to cut them down, but I have no idea what size is best.  Of course, I could use them as is, but my wife wouldn't like it one bit.

I have 16 exciters, but I could use less, or buy more, whatever gives optimum results.  I plan to experiment a lot.

[FullRangeMan]

I have two panels of Gatorfoam, each 4' x 8'.  I plan to cut them down, but I have no idea what size is best.  Of course, I could use them as is, but my wife wouldn't like it one bit.
I have 16 exciters, but I could use less, or buy more, whatever gives optimum results.  I plan to experiment a lot.

UHH!  You have two full sizes GatorFoam panels!!  So if you will cut the panels I can not help in this small panels sizes/exciters.
But if you could use a large panel, I can give you my owns plans for my project.
This is:  Panel wide= 75cm, panel High= 196cm  (Golden Ratio)
All eight exciters in the vertical middle like the Podium, Final Impedance= 4 ohms, Serie-Parallel (set 1, parallel=8+8+8+8=2ohms, set 2, parallel=8+8+8+8=2ohms, total= 2+2=4ohms)
Exciters Positons, Option ONE= first exciter at 21cm from bottom (21, 42 63, 84, 105, 126, 147, 168cm) rest 28cm to top.
Exciters Positons, Option TWO= first exciter at 23cm from bottom (23, 46 69, 92, 115, 138, 161, 184cm) rest 12cm to top.
The middle of the panel is 98cm, keep it away of exciters!!
My project for eight exciters this is it!! Anyone fell free to comment...
Dear Henry:  Another option: In 1987 I kickout my first wife for want command in my audio hobby.

[HenryPercy]

UHH!  You have two full sizes GatorFoam panels!!  So if you will cut the panels I can not help in this small panels sizes/exciters.
But if you could use a large panel, I can give you my owns plans for my project.
This is:  Panel wide= 75cm, panel High= 196cm  (Golden Ratio)
All eight exciters in the vertical middle like the Podium, Final Impedance= 4 ohms, Serie-Parallel (set 1, parallel=8+8+8+8=2ohms, set 2, parallel=8+8+8+8=2ohms, total= 2+2=4ohms)
Exciters Positons, Option ONE= 1? exciter at 21cm from bottom (21, 42 63, 84, 105, 126, 147, 168cm, rest 28cm to top.
Exciters Positons, Option TWO= 1? exciter at 23cm from bottom (23, 46 69, 92, 115, 138, 161, 184cm, rest 12cm to top.
My project for eight exciters this is it!! Anyone fell free to comment...
Dear Henry:  Another option: In 1987 I kickout my first wife for want command in my audio hobby.

Thanks.  I'll give those a try, but it will be next week until I'm back home.

[HenryPercy]

Thanks.  Mine are black, but I don't see any cardboard disk attached.

[Donka]

Zygadar,

Why no CA glue, I'm not talking cheap Krazy Glue, but engineering grade surface insensitive 5000Cp stuff?  Did you try it and it sounded different?  Just curious because Tymphany instructs people to use it to adhere their exciters.  Since I couldn't get the tape in time I had pretty much reserved myself to the glue route, but if it truly is sonically worse I won't use it.

Thank you for the detailed exciter removal and prep description!


EDIT:

Well, I just ordered some tape overnight, so I'll let you guy's know if there is an audible difference between glue and tape.

[Copperhead]

Hello everyone. I'd like to add my thanks to Ziggy for the work he's put in.

Ziggy, it seems from the DIYaudio thread that you used the Sound Pads. Apart from the impedance difference, do
you know how they differ from the Dayton units? The reason I ask is that looking at a Chinese manufacturers
website shows a dozen or so 25mm models, but their free air resonance varies between 230 - 500Hz. Are there
any specifications on the two models most of us are looking at.

I know no one has tested these panels yet, but could you play a low frequency test signal through them, and give
us a ball park figure of how low they can usefully go?

The other thing I noticed was the white Gatorfoam has superior compression strength, elastic modulus and bending
strength for the same weight, compared to black. Probably unimportant , but if colour isn't critical, white may be
better.

Has everyone given up on using a spline? Although it adds somewhat to the complexity, it should, surely, be better
than just hanging the exciters off the panel.

Does anyone have any idea how Podium have implemented their "Sound Bridges". Are they edge or surface glued to
the panel? Are they rubber? Perhaps they could be made in two halves and glued together, clamping the frame at
four random (?) positions around the edge.

I've got millions of questions and no answers. Can't wait to get this project underway.

[HenryPercy]

The reason I ask is that looking at a Chinese manufacturers
website shows a dozen or so 25mm models, but their free air resonance varies between 230 - 500Hz. Are there any specifications on the two models most of us are looking at.

Pardon my ignorance, but what does "free air resonance" mean?
Never mind. I found it.

The other thing I noticed was the white Gatorfoam has superior compression strength, elastic modulus and bending strength for the same weight, compared to black. Probably unimportant , but if colour isn't critical, white may be better.

Interesting.  Could you post a link to that information?  Thanks.

[Copperhead]

Hi Henry, Fs is the frequency of maximum impedance, and is usually the point at which the output begins to
roll off. As a general rule, the lower the Fs the better for low-frequency reproduction (not always the case
though, because other parameters affect performance as well).

http://www.alcankapa.com/alcan/acsites.nsf/pages_acde_en/index.htm!Open&p=services_download_gatorfoam&m=5&type=.htm
download technical data sheet.