DIY Flat Panel Speaker Love

[donradick]

Re: DIY Flat Panel Speaker Love

Your welcome Don...glad you got them done and making some music! Nice to have a DIY project that you can complete in a hour or so.

Just curious how far out into the room did you position them? I had to move them from my small listening room out into the living room. They need even more room to breath than my open baffles... at least 3 ft. into the room. Also need to find a way to be sure they are not over damped by what they are sitting on but a little is fine so that they are not vibrating on a hard surface.
...............
My panels took over 30 hours before they started to sound good. I'd say that a few more days for the panel treatment to cure and the exciter to break in would help improve the sound but I'm not sure how much given that specific exciter (plus gluing on with hot glue, unless you put it on really, REALLY thin... it will further rob detail and HF response) I'm not sure how much improvement is yet to come. The panels continued to improve over a weeks time.

If you didn't get them out into the room give that a whirl. Either way, report back if those panels open up with time Don!!

My wood shop is a corner of the basement with visqueen sheet "walls". The panel are hanging about a foot from the sheet.
I've got 2 more exciters - I want to try them with some 1/2 inch plywood and other materials.

[rmeinke]

Re: DIY Flat Panel Speaker Love

Howdy Don, now that's a cool application of a panel!! And the exciters should be durable in a dusty environment. Are you getting decent bass a foot away from the wall?

Its fun to play with different material. Cardboard actually sounds nice when treated with shellac. The high freq. start rolling off around 10K but is really nice sounding.

For a plywood I'd go thin unless your making a big panel. 1/4" thick seems to be poplar for larger panels (2'x5'). I think the exciters that you have might work better on a harder panel like a birch ply. Those exciters are sources from Visaton I believe and are well made but just not good sounding on a very light panel material like XPS.

Wood ply has good(smoother) LF performance compared to XPS but the HF roll off even sooner than cardboard so would need some HF support. I'm considering a 24 x 34 ply panel with a center mounted tweeter like the ND20FB-4 with a simple filter crossed high just to augment the panels. Panels would run full-range. Interesting to hear how that configuration would sound. I think they would have ample amounts of DML panel love!

[spasticteapot]

Re: DIY Flat Panel Speaker Love

There's an old model airplane trick that might work for these. (Actually, there's a lot of model airplane tricks that might work for these.)

A cheap-and-cheerful way to add a rigid skin to foam wings (usually cut from a core of Dow insulation foam) is to wrap them in butcher paper. I think the glue of choice was diluted Mod Podge. Strength to weight ratio is pretty good - butcher paper's cross-ply fibers are pretty strong, especially with a little glue.

If you're feeling really fancy, you can laminate the foam with extremely thin (1mm) balsa with the grain on one side running perpendicular to the other.

Just started to listen to the new Dayton Audio DAEX32EP-4 Thruster and it is a SIGNIFICANT improvement from what I (and almost everyone over at AudioCircle) have been listening to [until very recent]. Wow!

May we have some pictures?

[rmeinke]

Re: DIY Flat Panel Speaker Love

There's an old model airplane trick that might work for these. (Actually, there's a lot of model airplane tricks that might work for these.)

A cheap-and-cheerful way to add a rigid skin to foam wings (usually cut from a core of Dow insulation foam) is to wrap them in butcher paper. I think the glue of choice was diluted Mod Podge. Strength to weight ratio is pretty good - butcher paper's cross-ply fibers are pretty strong, especially with a little glue.

If you're feeling really fancy, you can laminate the foam with extremely thin (1mm) balsa with the grain on one side running perpendicular to the other.



May we have some pictures?

Hey whats up Teapot! Some have wanted to build an entire panel from balsa. Supper light weight yet strong. But the idea of making a panel of balsa seemed daunting.

The paper faced panel seems like a good idea. Some folks tried different combinations... paper, thin foil, etc. and didn't have great results. The original gator board has a foam core and some type of wood face and that worked okay but they have been discarded for shellac treated cardboard(needs HF help), EPS/XPS or birch ply(needs HF help).

When we are listening to the panel, we are listening mainly to the panel's "skin". The thinner the better it seems so even a lightweight paper has a pretty large impact on the sound. Its amazing to hear the impact that a 1:1 water diluted PVA (white/wood) glue has on the sound. Thin as hell but it damps the panel well and after hardening it improves the HF response. Shellac is said to over damp the panel.

I'll get pics tonight... ugly as hell but I'll try to get them posted tonight!

[EDIT] Don't mean to sound like its all been done before so don't try other panel materials and treatments. Experimenting is really easy to do as you can put together panels pretty fast and if you use VHB 3M tape while prototyping it easy to take exciters on and off. And more importantly... its FUN!!! Never had some much fun playing AND listening!!! Thanks for the suggestions!

[laserpaddy]

Re: DIY Flat Panel Speaker Love

Pics?

[rmeinke]

Re: DIY Flat Panel Speaker Love

Here are the smaller 24 in. x 30 in. 1" thick XPS panels with the new Dayton Audio DAEX32EP-4 Thruster exciter. Excellent in every way.

Beauty is only a light switch away...


Can't get more than this first pics posted. Will try again later.

[laserpaddy]

Re: DIY Flat Panel Speaker Love

Sweet thank you! Have a local artist do some painting....just a thought

[rmeinke]

Re: DIY Flat Panel Speaker Love

Welcome.

I'm going to build a frame around them and cover with quality grill cloth. They need to be properly suspended in a frame... they sound better that way. Always loved the look of electrostatic panels like the classic Quad ESL 57... beautiful...



But until then...

[donradick]

Re: DIY Flat Panel Speaker Love

Howdy Don, now that's a cool application of a panel!! And the exciters should be durable in a dusty environment. Are you getting decent bass a foot away from the wall?

Its fun to play with different material. Cardboard actually sounds nice when treated with shellac. The high freq. start rolling off around 10K but is really nice sounding.

For a plywood I'd go thin unless your making a big panel. 1/4" thick seems to be poplar for larger panels (2'x5'). I think the exciters that you have might work better on a harder panel like a birch ply. Those exciters are sources from Visaton I believe and are well made but just not good sounding on a very light panel material like XPS.

Wood ply has good(smoother) LF performance compared to XPS but the HF roll off even sooner than cardboard so would need some HF support. I'm considering a 24 x 34 ply panel with a center mounted tweeter like the ND20FB-4 with a simple filter crossed high just to augment the panels. Panels would run full-range. Interesting to hear how that configuration would sound. I think they would have ample amounts of DML panel love!

I very much like something about these. Lots of imaging, very wide soundspace.

[rmeinke]

Re: DIY Flat Panel Speaker Love

The wife and kids are out of the house tonight so have some panel lovin' going on right now. Listening to Chris Isaak - San Franssico Days. I forgot what a good recording it is... and a fine performance by CI. Excellent.

A couple observations:
1. Said this before, but I prefer small DML panels for speed, detail and upper bass/lower mid-range but the 24x30 panels are just not tall enough to enjoy the focused response of a line array (can sit closer). There is a REAL advantage to the radiation pattern of a line array. You move INTO the recording space so to speak.

2. For disclosure...it has been a long time since listening to this recording. But I am hearing more layers in the soundscape than I ever remember hearing. More nuances and shading around sounds. Because the panel move so very little I believe that it is able to resolve more detail than typical dynamic speakers in a box. Felt that way about electrostats but with these panels being fairly sensitive 90db+(guestimate) they are more dynamic and resolve a bit more from what I recall. Its been any years since I've listened to an electrostat so its not far to compare but in any event... the detail on this particular recording is resolved *very* well. All in a very natural, non-fatiguing way however. A joy to listen too!

If anyone in the Fox Valley wants to stop over for a quick listen your very welcome. Anyone passing through actually...just PM me and we can take them for a spin!

[rmeinke]

Re: DIY Flat Panel Speaker Love

I very much like something about these. Lots of imaging, very wide soundspace.

Oh Don... same... and just wait to you get them out into the room, the panels cure and you swap out to the new exciters. They have a sound that is so non-fatiguing yet highly resolved. I am freaking out right now actually listening to Chris Isaak. I've played it front to back twice and on my 3rd round. Bliss.

The more you listen the more you like and just hear more and more and more in old recordings that you didn't know was there. They are FUN to listen to!

And you mentioned it too. When I typically listen, I analyze my speakers and question if I should lower the tweeter level just a tad, can the bass alignment be improved, etc., etc. NOT WITH THESE. Never crosses my mind... just sit back and enjoy the MUSIC!!

[Squidspeak]

Re: DIY Flat Panel Speaker Love

Rmeinke, thanks for the kind and encouraging words about my Hestia project awhile back. Do you think your project holds any promise for
outdoor applications. I'm pretty sure there are exterior units from Dayton. Outdoors is a whole new ballgame compared to your indoor research.

[rmeinke]

Re: DIY Flat Panel Speaker Love

Hey Squid!!

I have heard good things about Tectonic's Pro stuff but never listened to them myself. Large venue Pro territory sure but if your talking about hanging a set of panels under the eves of a garage or house I'm afraid the LF won't develop fully. They do need space... more space than even our open baffles. Wasn't until I moved then into the living room did I really start hear their potential.

What did you have in mind? Anything specifically?

[rmeinke]

Re: DIY Flat Panel Speaker Love

I'm curious - how do you determine (1) the best dimensions for a panel and (2) the best location for an exciter on the panel? Is ther a simple process involving calculations, or is it all "by ear"?

To answer Brian's question from another DML related thread...

1. Panel Dimensions/Ratios: (ratio pulled from the NXT thread over at AC by user XIT)
- Golden Ratio (seems to be Tectonic's ratio) is 1.134:1
- Silver Ratio (from NXT patent) is 1.37:1
- Ratio from tech notes is 1.41:1 (Tectonic's tech notes?)

2. Exciter Positioning:
- PE Tech Note: Understanding Exciters – Principles and Applications
- Monacor Placement

I personally have used only 1 exciter per panel using the Part Express guide which is 3/5th of the panels height and width. Using my 2 ft. x 2 ft. panel the single exciter is placed 14.4 inches from the top and 14.4 inched from the left or right of the panels edge (I build them in mirror imaged pairs).

If I were to build my 24 inch width panels correctly, the ought to be roughly 32.75 inch tall using the golden ratio.

[Wolf]

Re: DIY Flat Panel Speaker Love

The Dayton Audio DAEX32EP-4 Thruster is the one I was considering. 40W power handling, and the durable steel spider. Are you using more than one on your panels?

I have tried the 4-arm models from Sonic Impact WAAAAAYYYYY back, and they sounded quite nice on some of this:

http://www.jm.com/content/dam/jm/global/en/building-insulation/Files/BI%20Data%20Sheets/Resi%20and%20Commercial/BID-0151_AP_FoilFaced_DS.pdf

I'll have try the glue or shellac on it to get it damped, but I have some of this still in-house.

Last summer at MWAF they had these "Bongo-ties" in the contestant giveaway baggies, and I think they would help suspend the panels well. Another option would be golf tees and bands.

http://www.platinumtools.com/upload_doc/1371583296BongoTie_PF_ONLINE%20%20TS.pdf

I'm thinking about it....
Wolf