A Study of DMLs as a Full Range Speaker

I just have trouble with the DML's being more sensitive than my bookshelfs so there's that.
So have you wired your Cones and DML's off of the same amp then ?

A second amp I found useful to overcome this, sometimes I use a Y cable to feed both amps the same signal and sometimes if I'm using my old yamaha amp I use it's headphone out to feed into the second amp.
Been doing it for years now, best of both worlds.
Where do you place your DML's ?

I have been placing them at the 2 corners of the front wall of the room, with the edge of the panel facing the listening position, and it makes it sound a lot like the front wall is not there. Yesterday I moved them to the rear 2 corners, also edge on to LP, so far I'm liking that even more, the spaciousness has moved from the front of the room to all around the room. I'm not yet sure if the spaciousness is as strong, more listening to do.
 
My motto is talk is cheap stop talking the talk and walk the walk.
Sorry man many are new here and want to learn. "A picture is worth a thousand words" and "talk is cheap", as they say. Not saying you aren't an expert compared to me and others. The reason they ignore what you say is, this is DIY and sharing designs helps others learn faster, design and share their designs, rather than repeating mistakes and hiding successes. If you have a proprietary design share it with the USPTO and stop blabbing on a DIY site. Who knows where the music you are playing comes from. OTS DMLs or pistonic speakers maybe, can't really ascertain about walk just listen to a video and read talk. Why use video at all?
 
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My forth post on this thread so I'm not doing much talking just trying to learn. You might as well tell me about religion if you are not sharing designs. You are the guy that's talking a lot. We know what you think that is clear but what did you make? Here is a fact: after age 50 your hearing is dramatically less competent so measurement is more accurate. Hearing is important but aural memory is inaccurate and any perceived blemish or feature will show up and documented in a Frequency vs SPL plot. Only asking you to associate a design with the sound on DYI site and why make video if all you sharing is the sound. I'll read the pamphlet but maybe not answer the door next time. Thanks for taking the time to respond in your previous post. Over and out.
 
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IMO, Audiofrenzy just cannot not be the center of attention. He is already run off the best source on here of DML technology, Spedge.
My question to Audiofrenzy is this: why are you so guarding of your system? Do you sell copies of it, or are you being approached by manufacturers to manufacture them? If not and it is so good, why are you so jealously guarding their design? Inquiring minds want to know.
 
Two interesting sites. One is a simple model you can try
https://www.dynamicmath.xyz/chladni-patterns/

If Solid Works CAD will run Cosmos CAD I will run models of my and others designs chladni patterns. We can correlate the output to frequency/spl curves and plate material specs and dimensions. I'm Just getting started and plan to share all of my work. Sorry if this redundant there 550 pages to read here. I'm an ME with 45 years of experience.
 
Once again I am not the one who ran off Spedge as Spedge and I agree on many of the same things. I also said that Spedge is one of the sharpest person on here. Now unless Spedge PM's and says I am the one that ran him off I will gladly apologize to him.

My question is WHY DO YOU CARE SO MUCH about my system? I dont ask you anything about your system.

Also I am the center of attention because no one is offering anything as I am the only one actually doing DML's.
AF - no doubt you have a lot of experience, knowledge and common sense. You've made a lot of contributions to this forum. My concern is that sooner or later your hostility and lack of humility drives everyone away or you get kicked out. This can be seen on the Partsexpress tech talk Flat Panel Love forum - soon you are the only one posting. Do you realize many of your posts can be found by just searching SMDH? I too wish you'd share the contruction details of your panels. They sound good, so they'd be copied in detail, be measured, recorded and tweaked. Those results would then be shared, to further improve them - to the benefit of all. Isn't that why we're here? Why ARE you here? If I were you, I'd rather be known on this forum, for your generosity, patience and skill - than what I know is going through the minds of others reading this.
 
I'm Just getting started and plan to share all of my work.
thank you Tim. I think we all try and share.... in our unique way 🙂 that's what makes it interesting..... at times.....

One thing I got from that video is, be aware of where you put your finger, or in our case, our suspension. I never quite understood the following picture until I watched that video. Symmetrical suspension placed non Non Symmetrically 🙄

Predicted-force-response-of-the-exciter-with-1-V-rms-electrical-input_cr.jpg
 
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With the cosmos program we should be able to model loaded plates with blended multiple frequencies (music) and exciters at once and see the patterns and correlate to data generated from REM and similar programs from actual prototypes. The number of iterations to good sound will be less and different plate material and shape properties can be simulated adding in measured properties. From what I read here and other sources deep bass will hard to get. I'm working on getting a cheap used copy of the program and ordering exciters and plate materials from McMaster Carr.
 
With the cosmos program we should be able to model loaded plates with blended multiple frequencies (music) and exciters at once and see the patterns and correlate to data generated from REM and similar programs from actual prototypes.
Timcognito,
It's great to see yet another person interested in taking an engineering approach. You may find this thread interesting if you have not already seen it:

https://www.diyaudio.com/community/...-dml-design-and-analysis.383567/#post-6954047

It would be particularly interesting perform simulations with exciter(s) on the panels. My simple FEA software (LISA) won't go that far. After taking a quick look at the COSMOS literature, it looks like you'll need the Advanced Professional version to do that.

One thing to think about if you want to model actual panels is that you will want a program that can handle orthotropic materials. As I have come to learn, the vast majority the panel materials most of us use are orthotropic. That includes plywood, carbon fiber (or fiberglass) sandwich structures, and XPS, corflute, balsa, etc.

Eric