DIY Flat Panel Speaker Love

[dawnut]

Acoustic guitars, awesome. I thought of that too. Glad someone did it. Guitars should be roughly same range as human voice. Interesting.

Trying to get the whole setup together pairing them with a small sub, when done I'll dig out a couple of my mic's and try to capture some decent sound video of them to share.

[Roadsterdriver]

Acoustic guitars, awesome. I thought of that too. Glad someone did it. Guitars should be roughly same range as human voice. Interesting.

[Roadsterdriver]

My designs are basically a modified version of Bertagni loudspeakers....Standard Design foundation would require a frame that would hold the diaphragm material in place with a spline to hold the exciter magnet in place as one unit like a conventional speaker basket similar to a BMR driver.

Material of choice is High density (EPS) Expanded Polystyrene. Preferred thickness 1/2-1/4 inch.....size ideal around 20-24inch X 16-18inch.

Frost King rubber foam to attach diapharam material to frame.

Oh, thin material...interesting design.

Do do you have any pics

[dawnut]

Love this thread.. SOOO much to digest.

Do you know if anyone has tried coating XPS panels in a thin layer of epoxy resin ? If I had to guess this might add a little more weight to the panel, but 'm curious if its a viable option. I am an artist and considering putting artwork directly on the XPS panel, if its been tried with no success I'll reconsider my options. If no ones tried I'll roll my sleeves up and have a go.

An alternative could be a water based rattle can spray paint. I know Krylon makes a water based spray paint just for plastics that you could give a thin even base coat with. They also make a primer just for foam products. https://www.krylon.com/products/craft-foam-primer/ That might be a viable alternative to the glue/water mix.. they also make a spray gesso https://www.krylon.com/products/gesso-spray/ . One of the nice things about working with the XPS panels are that they are inexpensive enough to experiment with. Grab a 4'x8' piece cut up some panels and go for it. I used regular spray paint on one of my experiments but you must keep the can a good ways away from the panel and use very light coats or the solvents will eat into the XPS.

[Unbiasedsound]

Coating the whole panel of XPS will not only add some weight to it but dampen the panel reducing volume out put and sound quality....unless you can dilute the epoxy to where its similar to the 50/50 water glue mixture....That would probably require some type of thinner like acetone or laquer but those type of solvents do not do well on polystyrene due to there corrosive properties.

[benjicon]

"You would still need to do the basics like sanding panel and treating the panel with 50/50-70/30 water glue ratio and rounding the corners painting the front side etc. you can read up on that on this topic."

Love this thread.. SOOO much to digest.

Do you know if anyone has tried coating XPS panels in a thin layer of epoxy resin ? If I had to guess this might add a little more weight to the panel, but 'm curious if its a viable option. I am an artist and considering putting artwork directly on the XPS panel, if its been tried with no success I'll reconsider my options. If no ones tried I'll roll my sleeves up and have a go.

[dawnut]

I'm a big fan of the DML, and have actually read through this whole thread. Being an old guitar player/builder I tried something a little different. Did a pair of dreadnought size acoustic guitars with the exciters mounted under the bridge area. I use these routed from my computer through a 6n3 YuanJing preamp and an older modified Lepai 2020A+ I'm using these in my 15'x20' sound room so volume doesn't have to go that loud.. Did my first listening session about a week ago with one mounted on a floor guitar stand and the other just propped against a chair. Amazing sound with details high and midrange that I have missed even with the PreSonus Eris E8 studio monitors I use with my DAW. Heavy bass at louder volume will get a little muddy and boomy so am working on a solution to that. with inline high pass and a small subwoofer. Still need to install my 1/4" strap peg jacks and hang them from the ceiling. I'm convinced these will be the speakers I'll be listening to just to relax by.

[Unbiasedsound]

It worked out pretty good...Still some kinks that need to adjust but all in all its to my preference.. After using 4 different conventional cone subwoofers I kept on going back to my DML sub.....A DML sub will not hit as hard, go as low or play as loud as a conventional cone subwoofer because of there limited pistonic movement....The reason why I prefer the DML sub is because IMO it blends the best with my DML panels keeping that DML signature sound....The DML sub IMO is also very articulate and detailed unlike some one note subs.

My designs are basically a modified version of Bertagni loudspeakers....Standard Design foundation would require a frame that would hold the diaphragm material in place with a spline to hold the exciter magnet in place as one unit like a conventional speaker basket similar to a BMR driver.

Material of choice is High density (EPS) Expanded Polystyrene. Preferred thickness 1/2-1/4 inch.....size ideal around 20-24inch X 16-18inch.

Frost King rubber foam to attach diapharam material to frame.

Driver recommended for sub application> https://www.parts-express.com/dayton...-4-oh--295-240 https://www.parts-express.com/dayton...4-ohm--295-238 If you need a 8ohm>https://www.parts-express.com/tecton...citer--297-206

Any type of sub amp. One with a 30hz boost or eq is a good option to have as most exciters low frequencies start dropping at 100hz

Tips> DML sub panel should be placed horizontally on the ground and inbetween the Left and right main/front channel speakers.

Using some type of acoustic foam pads like Auralex isolation pads under the DML sub will tighten up and increase bass response.

Using XRK's (DIYAUDIO forum) foam core enclosure on the DML sub will also increase bass.

You would still need to do the basics like sanding panel and treating the panel with 50/50-70/30 water glue ratio and rounding the corners painting the front side etc. you can read up on that on this topic.

[Roadsterdriver]

I just finished my last dml flat panel today which was the sub panel.......Sub is 21inchX16inch

How did the sub workout? How did you build it? Material, driver, etc?

[Vinaudi]

I am interested in DML. I would like to explore various hanging options for XPS. I am thinking of a free standing solution.

I am also interested in ways to power them at the source so a signal can be pushed wirelessly.

Ideas?

[Unbiasedsound]

This new Lepai 2.1 amp is what I needed for my (BASTAT) DML satellite/sub combo panels.

https://www.parts-express.com/lepai-...3118--310-4002

[nnjones]

You seem to be on the right track.....Best results I have found is to mount them to a spline/brace attached to a frame....if mounted securely very little energy is transferred to the frame as the voice coil will push against the magnet which will be stabilized in place by the brace and almost all of the energy will be transferred to the panel....you can use silicone or epoxy glue....I prefer epoxy.

Cool, that makes sense to me, thanks.

[Kornbread]

I eventually hung carboard panels from the ceiling with string before abandoning the experiment. It started with blue insulation board (xps) mounted in a frame, don't remember what size, but big. Eventually wound up cutting the edge of the foam board leaving only small tabs holding the foam board into the frame. For the most part it resonated freely from the frame. The freer the foam became, the more bass it produced. The exciter was mounted to a brace running behind the foam board which also increased bass output. Most of my experiment, including measurements, and the model number of the exciters which, at times, wouldn't last long enough to get a measurement, should still be on this thread minus pictures that Photobucket hosted.

[Unbiasedsound]

You seem to be on the right track.....Best results I have found is to mount them to a spline/brace attached to a frame....if mounted securely very little energy is transferred to the frame as the voice coil will push against the magnet which will be stabilized in place by the brace and almost all of the energy will be transferred to the panel....you can use silicone or epoxy glue....I prefer epoxy.

[nnjones]

Hi all,

I've been reading the threads on DML panels and am thinking about building some.

Here is what I have envisioned:

Dayton DAEX30HESF-4 drivers, 2 per channel in series, two panels per side vertically stacked (EPS or XPS?) 1" thick, 24" x 32", corners rounded, sanded and treated, mounted in a frame using foam weather stripping insulation as a suspension.

Should I mount the driver frames onto a spline/back brace, leave them free standing, or screw them down to the foam panels? It would make sense to me to fix them to a spline/brace so more energy is transferred to the coil/panel, and they would not have coil sag, but mounting them would cause more energy to be transferred to the frame (maybe silicone them to the brace?)

The rest of the details I'll work out around the crossover/DSP but any suggestions or advice would be appreciated.

I'm located in Fox Cities, WI area and noticed there are others that posted on this forum that are nearby, it would be great to hear from you.

Regards,
Nate