More Epic DML #4 - BMR Positioning
Vložit
- čas přidán 12. 09. 2024
- Just a quick update this time - I decided that it wasn't ideal having my HF drivers perched on top of the speaker, so I 3D printed a solution to get them a bit lower down onto the panel.
Not mentioned in this video (sorry) but I did also have to time-align them in the DSP, as the BMRs now sit a few cm in front of the panel. Luckily, the Hypex software makes this easy, as shown in my 'Basic Tuning' video!
Good video as always Ben, have you thought about adding wave guides to your tweeters ?, may help the tweeters dispersion even more.
Thank you! Yes I have. I wanted to start with the drivers 'bare' and then try a few different things regarding waveguides but right now I'm not sure what direction to take with these...
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.)
Yeah I can see this point of view for sure. I suspect that the lack of very HF is a function of the panel material (the acrylic seems to be quite well damped internally) so the options would be to use a different material or supplement with another driver. I don’t mind the complexity overly much if it sounds good.
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
Wow interesting. I'll have to start playing around with this when I get the chance.
@@TypicalBenYT i wasn’t even actively looking for a new material but I picked the box up and was like wow this is super sturdy for being so light cut the bottom out and a 2 foot by 1 foot section weighs nothing but it sounds like an oak board when I knock on it.
@@TypicalBenYT 243-EX80S-8OHM look that up on mouser electronics. It was recently linked to me by someone that’s doing something similar to what you’re currently doing. They said it’s the best sounding exciter they’ve tried thus far
@@TypicalBenYT that visaton brand is also on parts express. a few models anyways. not sure if its the same one i suggested
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.
Interesting thanks for that! I might have to play around further to see what happens!
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.
Not sure if something fibrous would be ideal. I would assume the foam board that does "the best" does so partially because it's porous, and the plexi/lexan does well because it's smooth/hard and consistent/homogenous. My terminology might be wrong, though.
@@Drunken_Hamster I would typically agree with you. However the panel I made yesterday out of a 3$ piece of canvas glued on to cardboard from dollar general sounds shockingly good. The outside is well coated and after cutting it it seems like the “tubes” inside are lined as well. I honestly thought it would be solid wax right through but it’s not. Because when I say rigid it sounds like I’m knocking on the side of a piano… like S O L I D. And that aspect plus I he tubes being hollow I feel like it’s going to allow the sound to resonate through the panel better. But who knows lol I just started making these a few months ago and I’m a highschool drop out that delivers antiques for a living lol I’m definitely not the authority on normal speakers let alone dml panels lol I appreciate the feedback back though!!
@@LikelyLagging I'm you but older and less successfully employed, so like. :shrug:
It'd be cool if you could make a video or take some measurements like Ben, here.
@@Drunken_Hamster successfullyis definitely a word than could be used lol unfortunately covid and fuel prices have basically gutted a 35 year old business that my father created. We are pretty much the only people that do it professionally and it was not incredible money but certainly enough to live decently. But now with fuel costing so much no one wants to ship anything so I had to get a part time job cooking. And I may have lucked out for a while and was able to work my father (don’t recommend btw, our relationship outside of work is awful) but I’m 30, with zero credit, no bank account and just moved into my own place with my fiancé. All on top of keeping what was once a raging opiate addition locked away. I ain’t judging 🤘🏼
shit happens and this too shall pass. If it doesn’t then we can just crank our bad ass speakers to 11 and say fuck the world lol
As far as video I could probably post something here or maybe on twitter @likelylagging. I don’t have a calibrated microphone to take measurements though. But it’s on my list right next to a DSP and a solid 2.1 blue tooth amp so I can stop moving my big ass 7.2 receiver around lol if any one could point me to a decent iOS audio measuring app I could def do that tho, or if there’s something free on windows 10 as I do have a pretty solid studio microphone. Still not calibrated but probably better than the iPhones
@@Drunken_Hamster my suspicions were correct. It’s by far the best sounding panel I’ve made so far.
first. I'm going to build those DML speakers if it's the last thing I do before I die
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)
Technically dipole, but with some bipolar behaviour (little to no destructive interference in DML mode). “Diffuse dipole” to use Tectonic’s terms. Even so the reflections may or may not be ideal
@@Butternose Has someone measured DML diffusion on & off axis front & back ? Hard to find any relevant. A flat pannel like would put nearly as much in front than in the back. Same for the Tektonic. Can't find the same type of measurements.
Garbage, even Bose is better...
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 :)