xsuper9988,
I used Walmart's 12x16" artist canvas. They are cotton canvas, and the wooden pad is rounded corner 4x6" 3-ply paneling sanded down on both sides to almost 1-ply thickness. I used the Dayton DAEX25FHE4-4 exciters. I used acrylic paint thinned 4:1 on both sides. 1 coat is enough to completely cover the white of the canvas. I put 2 coats on the front and 1 on the back. They were taut enough that I did not need to use the tightening wedges. A year later, they are still quite taut. I used a 12x1" slat as the brace for the exciter, with a thin piece of foam between it and the exciter. Mine will play 40 Hz quite acceptably if played at a moderate volume with no thumping bass. I had a 1kmf cap inline to limit the response at 60 Hz, but found that I did not need it, as I do not use very high volume.
I used Walmart's 12x16" artist canvas. They are cotton canvas, and the wooden pad is rounded corner 4x6" 3-ply paneling sanded down on both sides to almost 1-ply thickness. I used the Dayton DAEX25FHE4-4 exciters. I used acrylic paint thinned 4:1 on both sides. 1 coat is enough to completely cover the white of the canvas. I put 2 coats on the front and 1 on the back. They were taut enough that I did not need to use the tightening wedges. A year later, they are still quite taut. I used a 12x1" slat as the brace for the exciter, with a thin piece of foam between it and the exciter. Mine will play 40 Hz quite acceptably if played at a moderate volume with no thumping bass. I had a 1kmf cap inline to limit the response at 60 Hz, but found that I did not need it, as I do not use very high volume.
I listen to some wall mounted DML's every time the TV is on. I switched fairly recently from floor mounted yamaha's. Those now sold on. I had used them for rear speakers in the past. The panel is backed with a foam and then a vaccum formed plastic thinish cover ribbed to stiffen it but if I tap it no audible ringing. Frame size 555x500mm. Freq response quoted 80hz to 20khz but uses a sub woofer 40hz to 170hz with a simple one small capacitor cross over to each DML Stated to result in a cross over frequency of 160hz. 2 25mm exciters on each panel 70w
program power. Panels alone stated as ok for rear speakers but not front without the subwoofer.The foam has a simple oval hole where the exiters are and locally covered with pieces of acoustic wadding.
Thanks John!I listen to some wall mounted DML's every time the TV is on. I switched fairly recently from floor mounted yamaha's. Those now sold on. I had used them for rear speakers in the past. The panel is backed with a foam and then a vaccum formed plastic thinish cover ribbed to stiffen it but if I tap it no audible ringing. Frame size 555x500mm. Freq response quoted 80hz to 20khz but uses a sub woofer 40hz to 170hz with a simple one small capacitor cross over to each DML Stated to result in a cross over frequency of 160hz. 2 25mm exciters on each panel 70w
The foam has a simple oval hole where the exiters are and locally covered with pieces of acoustic wadding.
I like this. It kinda confirms I'm barking all around the right tree.
Questions:
1. Can you explain how "160Hz cross-over" relates to "80hz-20khz freq response". Do they mean that the panels go down to 80hz if you take out the caps?
2. I'm assuming those are 8-ohm drivers hooked up in parallel to give you 4-ohm load. This means they're using 120uF caps in line with each driver for -3dB around 165hz. Can you confirm?
Cheers.
Tricky at the moment as still having PC problems so can't test,
Just listen. Not done much recently on that thanks to a 16day trip to the north cape.The cross over freq confuses me too, One small cap in each panel isn't going to introduce anthing like a sharp cut off and they don't state the actual drops at each end of the freq responses. Might be 3db or 6. I can only assume that both the woofer and the panels emit over some of the range they cover but have no idea what components are used in the woofer. The panels are connected to that via separate leads. The caps I mentioned are in the panels - could be to just limit bass response when used as rear speakers. They make a point that bass power on front speakers is likely to be too much for them. That probably relates to the 70w program rating rather than giving an rms one. Sensitivity is 87db at 1m 1watt, Same as the woofer. The caps are rather small disk types. That means can't be uF. It's a passive woofer. Left and right go to it and out again to the panels.
They use 2 4ohm exciters in series. NXT. Interesting as I have suspected that 8ohm and exciters does not mix well. A little different to what Dayton say. I must have bought the stuff ~20years ago. Amps were rather different to what is often used these days.
It's seemed to me largely down to owning these that the effects of space behind them is an important aspect. Ideally it should not matter and can't be ideal if it does. Foam though - yet another complication. I'll delve further when the PC aspects are sorted and post what details I can.
North Cape?Tricky at the moment as still having PC problems so can't test,
This one?
Those are possibly PTC thermistors to protect the drivers from being over-powered. PTCs will go open circuit under too-high power conditions, and then reset after cooling down.
Two exciters in series will suffer a decrease in HF performance as coil resistances naturally increase at those frequencies. The problem is discernable with 4-ohm drivers, and obvious with 8-ohm drivers. Each coil will each see the series resistance of its mate, as well as the inductance rise, and will see correspondingly less drive voltage at HF where the series resistance gets much higher.
The remedy is to place a shorting capacitor across one of the two drivers. The correct value should be between2uf - 20uf depending on coil inductance. This means that the HF into that driver gets shunted directly into the other driver.
If you can measure the impedance of the whole cab, then you're looking for the inductive rise at HF to be flattened to a straight line. A too-big cap will cause the cab overall resistance to drop below the specified speaker impedance (8-ohms in your case?) at higher frequencies, say 10khz; a too-small cap will not make enough difference.
Of course, this whole issue becomes completely moot with drivers in parallel.
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This one - sun at midnight and never sets during this part of the year
https://en.wikipedia.org/wiki/North_Cape_(Norway)#/media/File:North_Cape,_Norway_-_panoramio.jpg
The panels - I'll not comment until I have tested them.
Leob.
The exciter mounting looks much better now, more robust.
Is there any chance that you could post some more videos of them in action?
I liked the ones you have already posted,it felt and sounded like I was there, maybe walking around the setup and the listening, dance area?
To get an idea of how they perform.
How about playing some jazz 🤣😂
Seriously though, they sounded very powerful and gave a good sound coverage, even in the distance.
Steve.
The exciter mounting looks much better now, more robust.
Is there any chance that you could post some more videos of them in action?
I liked the ones you have already posted,it felt and sounded like I was there, maybe walking around the setup and the listening, dance area?
To get an idea of how they perform.
How about playing some jazz 🤣😂
Seriously though, they sounded very powerful and gave a good sound coverage, even in the distance.
Steve.
Crazy how much weight, size/ease of mobility compared to traditional. Amps included.
Has anyone experimented with very long and narrow panels? I am thinking about creating a center panel for my sound system that fits under my projector screen. I use a UST projector so there is not much space. The other option would be to get one of those screens made for sound coming from behind, but that will hit the wallet much harder.
The size I am thinking of is about 6"H x 48"W. (15cm x 122cm)
I was thinking of Foam and/or Cardboard. I have been reading through the entire forum and noticed that some people talked about gluing or sealing multiple materials together to get a more natural sound. Does that actually work?
And for a panel that size what exciter would you recommend?
The size I am thinking of is about 6"H x 48"W. (15cm x 122cm)
I was thinking of Foam and/or Cardboard. I have been reading through the entire forum and noticed that some people talked about gluing or sealing multiple materials together to get a more natural sound. Does that actually work?
And for a panel that size what exciter would you recommend?