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If that cable is the cheap flex copper cable I would exchange if for a better one. Those cable are terrible in mid and highs. Consider the Argon Prime SC1 hollow cable, can be bought from ali also. A good price/perf upgrade.

You should look into Icepower amps…As1200s2 is a beast of a plate amp…There is a youtube channel that did a deep dive on these amps, a really really deep dive😂 th-cam.com/video/zSsy41UlqF0/w-d-xo.htmlsi=kPb4nn5xGchlxzUw

Wow. You have inspired me to THINK about making a pair of Goldies.

Hi Ben, Guitar luthier here. Great work. About the bracing, it's has multiple functions that you didn't took into consideration, especially the main one : helping the membrane to resist to the string tension (about 80kg for a steel-string guitar). So it needs to be extra extra stiff to avoid complete deformation of the top under tension. Using a thicker membrane make it too heavy to dissipate string energy efficiently so we use bracing to get stiffness and avoid extra weight. In your DML speaker you don't need them and adding them probably accentuate some resonance mode (I think you said around 200hz). If I understood well, a DML needs to have as few resonance peaks as possible. Another function is to compensate to orthotropic properties of wood which is much stiffer along the grain that across is. So bracing is designed to make it a bit stiffer in the cross-grain direction and balance the speed of propagation of the waves in the top. You wouldn"t need that either as acrylic is isotropic and homogeneous.

What software are you using for the analysis?

Enamel coating on the wire. If it is for crossover that means it can be coiled and that will require an enamel coating. I am sure there are other comments, I am a year late. Great videos BTW! I am starting a small business making custom DML and these have been some great videos to watch.

Hi Ben, Thanks so much for being this thorough! I see that you come to the conclusion that an exciter placed in the exact center, would arguably be the least effective placement for a second exciter. This is exactly the opposite of conventional wisdom I've come across during my research into this topic. I've also heard some a/b testing with 1 exciter (2/5ths , 2/5ths) and a second one dead center, and the latter actually sounded fuller. Perhaps this gives me my answer, as how I experience it is all that really matters for myself, yet I'm super curious what your take is on that configuration of exciters. Have you experienced it diminishing the sound as opposed to, say, your proposal for a diagonally placed 2nd exciter?

As far as light and stiff material goes, carbon fiber comes to mind. Any thoughts on how a sheet of carbon fiber would perform?

Needs a subwoofer.

Is it possible to find "Bamboo plywood" in the U.S.? Never have seen any......

Any plans for open baffle sub setups ?

I wonder if bass shakers can be used for bass freq on a panel. Something like the dayton bass shaker which is super powerful too 300w i belive. I bet no one has mounted that on a panel yet as a dml system. Maybe you can give it a try & give true sub duties to the 12" subs. & 80-200 to that dayton bass shaker on a panel. Also aperion makes some great amt super tweeters.

A very elegant solution, and solid execution, instant sub. People somehow think these should do it all, rather than just a driver with frequency limitations. The 600hz 24db sealed makes me wish I had a DSP, and not a 20$ P.E. sale amp. Someone below mentioned AMT tweeters. I just installed a set of the car audio version, in my truck (does have DSP, active 4 way) They sound amazing, and have a dispersion that could nicely complement the way DMLs "fill" space. The pro4 even has a removable back, if you wanted to run dipole(!) Or sealed. Playing down to 800hz, all the options for frequency and rolloff. The idea for the exciter tweeter tho! Got me wanting to go look in my box of future projects, and see if I have any minis in there... Nicely done sir, look forward to where it goes from here! Edit: found some 13mm coins in the box, time to stick one to I dunno... Maybe a CD to start.

If you present these graphs, please show the noise floor as well. Since all measurements are only valid if the speaker noise is X db more than the noise floor. Thank you.

th-cam.com/video/haKoMOiOqhod/w-d-xo.htmlifferent material

So my cast wax board suspicions were correct. The volume and clarity are leaps and bounds better than any polystyrene panel I’ve made so far. If you can’t find them online(if you do find them lmk where please) go to your local farmers market and see if they have any produce boxes they will part ways with. Thats all mine is. I cut the bottom of the box out. Used a bar of paraffin wax to fill in the now exposed the edge, along with any divots or weird spots along the surface, used a lighter to melt away the spot where I was going to mount the exciter put on several coats of super glue it out and let it dry and then put VHB tape on that and then attached the exciter, but I imagine you can probably just use epoxy

Thanks for this! Have you considered reversing the polarity of the subwoofer or chasing the phase at the crossover point?

Interesting! I can’t remember where, It might have been the forums or the tectonic engineers spoke of acoustic centres on dml. Although DML is immune to many traditional ills, it has been suggested that the radiating area reduces with rising frequency, also the initial impulse in the signal helps spacial localisation and imaging. If that is the case for critical listening you may want to get the bmr as close the panel exciters as possible. Any difference maybe more noticeable if your crossover slopes are shallow. The space between sources for interference at 10k is effectively nothing, In traditional speakers you would expect an interference pattern, but in DML it most likely manifests as a loss of imaging or just perceiving separateness.

good progress . . the slap echo in that room seems horrendous . .

Great video, the bass or low mids seem a bit absent. It might be the little Hotone mini amp is a bit shrill. Not that your speaker sounds shrill and no ice picky highs, its treble biased but sounds smooth so that's a great start. You could try running your Fender SS amp through the test speaker if the amp has a phono jack socket to plugin the speaker, just plug in your new flat panel instead. The panel seems very small to reproduce lower frequencies. I wonder if a bigger 500 x 1200 mm bass panel with a bass exciter hung behind the existing one might fill in the sound? You'd need a simple crossover too. There is a flat guitar speaker recently gone on sale from Eminent (not Eminence, different company), it's not much larger than yours.

I... tentatively feel like we're working backwards. I thought the whole point of DMLs was that they could handle everything from 125hz up to 16khz or so in a natural fashion. The whole point of MY research on audio in general is to have as few driver types with as wide, accurate, and natural of a response range as possible. Trying to tune and aim 4+ driver types is kinda a non-starter to me. I'd rather focus on broadening usage and off-axis performance so there's less to faff about with with physical setup. (I'm also focusing on car audio, and all that stuff (packaging in general, I mean) is by default more difficult in a car, hence my aversion to it.)

Good video as always Ben, have you thought about adding wave guides to your tweeters ?, may help the tweeters dispersion even more.

So I think I randomly stumbled upon what could be IN THEORY the fucking best material for dml panels ever… absurdly light and shockingly rigid. I plan on making one over the weekend and will try to remember to report back. Anyways look into wax dipped/coated corrugated fiber board. Not like pizza box cardboard but the double walled stuff. I haven’t looked for it online yet but fingers crossed someone has it incase it sounds good.. which I’m thinking it’s going to.

Hi, from what I have seen of that tweeter it is not so good in the frequency range that you want to cover. Also it's open back and he is having his backwaves directly reflected on the plexy right behind. I don't think that is an ideal situation. As DML is essentially a dipolar I would instead go toward a better dipole planar driver on top of the frame to be consistent. (EDIT: FYI I am using a Radian LT2 with Waveguide but I had to cut the back myself)

Have you considered covering your frame in flexible material then gluing the panels to the material. The material would act as a suspension mechanism, which would flex with the vibration. Potentially allow the mounting of multiple panels to the same material? Might look a lot more attractive also. Just a thought, although too be fair I've never built one of these. Just an observation after watching a few videos :)

first. I'm going to build those DML speakers if it's the last thing I do before I die

Esse cara faz experimentos científicos sonoros e nesse vídeo ele testou um monte de configuração, materiais, frequências, várias configurações justamente de som de ressonadores assim. th-cam.com/video/CKIye4RZ-5k/w-d-xo.htmlsi=tzcsZOHg3fQOmorB

th-cam.com/video/CKIye4RZ-5k/w-d-xo.htmlsi=tzcsZOHg3fQOmorB

Youve got th best unfo on dml speakers I could find on youtube. I am loving your videos. I pesonally built a dml speaker foe my living room, and used a 2x4 pannel of foam progect board painted to match th walls. Whwn i first tested it, i hung it from the wall, and was dissapointed by thw sound. So, I moved it to the corner of the ceiling and the entryway, lile youve got on the top right hand side of your house in this video. Once their the speakers sounded great, but lacked bass(as expected, I suplemented with an external sub). Anyway point beig i would loke to see some expeiements with differnt shapes and sizes for an enclosed rear box for your speakers

Has anyone ever tried to make a slightly concave face of the panels? Something to replicate a cone for a traditional type speaker. It probably doesn't have to be very deep, but a gradual change in face depth across the panel.

Informative and practical! Good job!

What program did you use to add delay on the panels?

The shirt got my like!

Have you tried a composite panel? Plastic core with very thin aluminum on both sides.

I like the acrylic panel better. I just finished my first acrylic experiment. Still tweaking because I used really thin pieces of acrylic. It's actually vibrating too much. Im only using 4 watt 4ohm exciters, 2 on each panel to get 8 ohns. I didn't see anyone using acrylic until today. I'm completely new to this. It's very satisfying . Ever tweak is an improvement so far😊.

Sounds like there is some cancellations going on like comb filtering. Also I hear some static noise just when you stood up? This is my DML>th-cam.com/video/00spcs18MeU/w-d-xo.html

Beautiful build! Around 10:27 you mention the BMR & DML acting as dipole, which you commented on in the video. DML panels operate as bipole in that front/back radiation is in phase. There is a reduction in output to the side of DMLs because of a lack of output from the edges of the panels and not not due to cancelation. A BMR acting as DML in high frequencies experiences this, but as frequency lowers and pistonic action takes over, those frequecies are dipole. So, a BMR has a mechanical "crossover", if you will, where low and high frequencies use different mechanics to produce their sound. It's not too different from a driver with a whizzer cone. Keep the videos coming!

You do know you can get rew to autogenerate the filters for you and import direct to minidsp.

Dome tweeters have great dispersion. They're a dome, after all.

Dude, your volume is all over the place in this video, mainly so low not audible... at least for me.

Are the next tweeters gonna be Air Motion Transformers?

I wonder how it would work out using 2 of those on each panel. Maybe go with one on each top corner and you could put some sort of cover that goes across to make it look more uniform.

noice

noice

Plywood as a resonant material is not the best idea. Example the cheapest guitars are plywood.

This is definitely not how you wire them together. Good idea but you cant run power thru a speaker. You have the positive from the first to the negative on the second then the negative on the second to the positive on the third. Then with 4 its even weirder with the ground not connected to anything but another speaker. Not sure how or why you did it this way but pretty sure you got this completely wrong and almost positive most of them wernt even working for your test.

Ben, Initially, I would like to commend you for your content and I particularly liked this build and the final result. I have a question for you if you are still monitoring this thread and inclined to respond. My Audio system consists of Denon 4311 9 channel audio visual receiver, Front speakers are JBL ND310ii (2 x 10 inch drivers, 4 inch Mid and a 1 inch titanium tweeter) Front surround and rear surrounds JBL TLX140 (single 10 inch woofer, 4 inch midrange and 1 inch titanium) 2 by JBL 10 inch subwoofers You may notice no centre speaker and 2 speaker channel not utilised as yet. My question is, I am thinking of using a DML panel speaker for a centre speaker now, and possibly 2 DML panel speakers to complete the 9.2 system in the near future. The plan is to use 4 x 40 watt Dayton Audio exciters and a JBL tweeter for the centre and possibly the same configuration for the front high speakers in the future. Could you possible advise whether the DML system is practical or even good for the centre and front high speakers. MY audio room is dedicated to music and is 4 x 6 meters with all the walls totally covered in 2 inch foam and that is also covered by a carpet. The only furniture in the room is a cabinet 2 meters long and 600 high for the audio components and a single arm chair centrally located for maximum surround sound. Very much Man Cave stuff. I am an Aged Pensioner and Australian expat living in Indonesia where the adivce is impossible to get. For that reason, any advice would be very much appreciated. Regards Tony Chilcott

Just keep having fun with it, please bye some cloths man.

Has anyone tried balsa wood? It is light and stiff. I am thinking of building a set for fun.