This is golden. It's not easy to get someone to explain such technical and precise concepts in a really simple way. I wish this was the case when I was at university. Brilliant.
It’s awesome to hear and understand all this as well as surprising you’re sharing all your secrets with us. I dont know of anyone else that does this as most inventors want to make a product and sell it to make money - but you’re dedicated to the DIY / Hobbyist… much Qudos to you
hope you can also discuss how to measure the response; software, type of mic, the distance of mic to measure driver/s... thx in advance Danny. Great topic and explanation.
Measurements are the most difficult aspect of speaker design. To do the topic justice would be hours and hours long. Then the software that takes raw calibrated microphone response and allows a person to make meaningful engineering decisions is another set of tasks that need to be completed. If you're serious about acoustic measurements the best way to get up to speed quickly is to have a competent engineer measure some devices in your presence and explain why he/she is doing something in a certain manner and/or sequence. The parts-express forum has lots of engineers that visit, but because they are aware of the issues with measuring, they may not be of much assistance. I happened to have learned from Dr. Joe D'Appolito as he lives only a few miles from me. There is a shortcut but it costs thousands of dollars and still requires knowledge of acoustics and attendant engineering principles. That would be a Klippel analyzer. Another engineer (I am an EE) that I know once said it takes a decade to learn the engineering required to self-validate results. I think that horribly pessimistic, but there are learning curves. I learned enough in two years of study to make good measurements. If you simply want a speaker design tested there are a few acoustic labs that do this in the US, and I personally know one company that provides Klippel analysis at low cost, and professionally another that would almost certainly provide free analyses for non-commercial use. This is not intended to dissuade anyone from performing what are, essentially, formulaic tasks. I just want people to make good measurements is all.
I built an open-baffle subwoofer a year or so ago and I like it so much more than any of the ported subwoofers that I've heard and owned. I'd love to get ahold of some open-baffle monitors! Thanks for the great video!
Great video. Really there is no magic involved just measure change, measure change until you get the best response. Provided you have the equipment to measure there is nothing stopping us doing this at home. And it keeps the cost of the crossover down as well. Really helpful tips.
Can you recommend decent affordable measurement equipment, software etc? I have a blue blueberry studio condenser mic not sure if it works for this application
Wow! Great explanation of your empirical development process. I had no clue about the details of aligning of the voice coils for proper phasing (front baffle thickness). Also the cutout on the short side to unload the high frequency driver and the non-orthogonal angle for the long side of the enclosure. I'm watching part 4 next. Thanks!
A note about KEF “Meta” LS-50: “Meta” is solving a problem unique to coaxial dome tweeters. Every good quality separate dome tweeter I’ve seen lately has a rear damped resonance chamber incorporated in the design.
That is literally priceless! As long as I'm in the process of designing my first open baffle speakers I'd be grateful if someone could answer a couple of questions: 1. SPL diagrams that was shown start from 200 Hz. What's going on below that frequency? I assume it slopes further down? 2. You explain how L-frame works. I'm curious if the T-frame works the same (i.e. if we put the long wing vertically to the center of the baffle back). I observe some open baffles are made this way 3. what's your advice on speaker mounting? Flush mount is the best isn't it? What if I decide to mount woofers to the back of the baffle, making the hole wider outwards like a short horn? (and keeping the phase issues in mind of course)
1. To measure accurately below 200Hz, outside of an anechoic chamber, requires being further away without reflections. That is not possible indoors. The low end roll off can be calculated and then confirmed with impedance and nearfield measurements. 2. A T shaped baffle does nothing to separate the front and back waves. It is nothing more than a brace. 3. Flush mounting is best.
I love my x-statiks; they put out a HUGE sound-stage. I do wish they were a little more transparent though for 2-channel listening. NX-Oxtica build is on my wishlist.
Used this info in my alnico/ neodymium build with stellar results, mine ended with 14” outer wing and 2” inner wing with upward facing rear mounted tweeters ♥
For a first try, go to a thrift store an buy some cheap 2 or 3 way speakers. Take them apart and mount all drivers in a baffle. You will be amazed. I did the same and listen to rhem for months right now. Sounds so much better. Gonna make a second set soon. Philips drivers from the 1970's are great.
Thank you for educating us. Please do some audiovisual clips from your sound room with your speakers without your servo subs.....I belive tin pan alley from the great SRV is a very good choice to play on your speakers....
Great as always! After years of diyaudio forum I started grativating around openbaffles. This video give so much theory in a clear and condensed manner it's just great! Would be interesting an episode discussing power dispersion response around the speaker in relation to the wings. Also your thoughts about the Linkwitz mini as I was thinking to build a pair :) Great work! Thanks, hope I'll be buying those servo subs soon...
Thank you, sir for your great videos ! I am curious about the horizontal axis frequency and acoustic lobe effected by the non-symmetric baffle. Hopefully you can do some videos on that too.
You should be a presenter at the Burning Amp Festival in San Francisco every October! During the summer Nelson Pass supplied open baffle kits for a speaker camp that was a lot of fun. I think there would be a lot of interest among diyers in what you offer.
I really really appreciate you taking the time to make these vids. What would be really interesting to me is off-axis response on these speakers. I'm not a fan of MTM in general because of the narrow vertical axis, I wonder how the asymmetric wings behave with the horizontal axis I have almost convinced myself to buy a pair of your sub-kits, looking forward to the next installment.
Actually not all MTM designs have a narrow vertical window. We have quite a few with a really wide window and even vertical off axis that is better than most two driver designs. And the asymmetrical wings will also help maintain a smooth off axis response.
I've always wanted to design my own speskers, so it's really interesting to see how these particular style and desgin works and how simple changes can effect things dynamically. So of course like all of the people who've watched this and the other videos, i'm my own theory; there is packaging you can get sometimes with products where cardboard is cut in a specific way so that when pulled apart, it creates a dimond pattern. If this was high strength material, like say Aluminium, and the negative spaces created had been filled with a sheet of say acoustic material, like Oasis, that material you can stick flowers in. and this sat behind the baffle (created by the Aluminium structure) with the Oasis filling the negative space; could you then mount a driver and tweeter, with possibe sides of similar construction, could this work, less structural mass to reflect but with some accoustic properties? Hope you don't mind me asking. Thanks.
Quick question on how to position these speakers: long back edge on the inside or the outside edge as seen from the listening position? Love your work!
The two speaker open baffle that you did the crossover for setting on top of a servo sub sounds like a nice package. Any plans to offer a kit like that?
That is a great result that can be achieved. In a two channel stereo, would the large wing be to the inside or to the outside? and what can be expected by swapping that over?
Actually they just made a diffuser for cancelling out the back wave. It's not at all new. And it is nothing compared to a tweeter that is completely open to the room.
@@dannyrichie9743 It doesn't diffuse anything, it absorbs the backwave by an array of 30 Helmholtz resonators and matching impedances from the tweeter to the metamaterial via a conical horn. You should read the AES paper to understand the design. But it only works on the tweeter so only above the crossover point. The rest of the critical midrange is not absorbed. It is for monopole speakers of course. Open baffles have a whole different sound being dipoles and not every person or application is desires that kind of sound.
Stewart Markley - “Meta” is solving a problem unique to coaxial dome tweeters. Every good quality separate dome tweeter I’ve seen lately has a rear damped resonance chamber incorporated in the design.
Now. What would happen if you have a U-shape baffle and use heavy lining of NoRez material inside that cavity to control those frequencies that stay within that area and cause that megaphone effect?
Great presentation. I follow the theory and one can not seem to contests the results as measured. This seems so different then the spatial audio designs. If I am understanding what Danny is saying then the Spatial Audio open baffle design should produce a radically different result. I would love to have Danny and Clayton Shaw discuss there respective approaches. Clearly, both are getting great results but with seemingly opposite approaches in the baffle design. Can they both be right?
Maybe Clayton and I will do something like that one of these days. And I wouldn't say that there is necessarily a right and a wrong. Objectives can be different and the highest performance or highest attained results based objectives might not have the value of a more marketable and commercially successful design.
I guess the room and placement in the room changes the response too. How far from the back wall is optimal vs possible placement to still get the most out of an open baffle design like yours?
On the application of the L frame, I wonder: aren't you changing the plane in which the back wave and the front wave cancel out? If the L side baffles would on the most extreme outsides of the speakers from the listening position, the zero pole plane would toe out, This phenomenon would be relevant for toe-in/toe-out positioning speakers to avoid first side reflections from the side walls. It might also influence the imaging between the speakers. What do you think?
@@dannyrichie9743 In a planar open baffle (no side wings), front and back waves are separated in the virtual plane where these meet in equidistance due to their opposite phase. For a planar open baffle, this virtual plane is obviously the plane of the baffle. By setting the toe-in exactly as indicated by Linkwitz (using his mirror approach), the first reflection side waves that bounce off the side walls of the room can be minimised. By placing a rear wing, the virtual plane in which these front and back waves meet in equidistance no longer coincide with front baffle plane. So, to get the same minimisation of side wave reflections, the toe-in of the speakers must be altered accordingly with this change of virtual plane. That was the point I was trying to make.
Roughly, What size side wings would be recommended for a 15” bass driver only, driver mounted center horizon. and 2” higher than center vertical, in a 21” x 27” Baffle?
Sir the 12 inch - 2 inch - 110 degrees works for all size drivers? Or as the driver size gets bigger needs bigger side asymmetrical drivers? And if yes have u figured a ratio between driver size and side baffle size? Thank u for your work and greetings from Greece. Have u ever shipped your speakers to Greece 🇬🇷 ???
Hi Danny, Thanks for the sharing knowledge and experience! I have a question. How looks the off axis response (left and right)? I'm expecting a non-symmetrical response... In case that the truth is, does it mean that for that kind of design, you get really a small sweet spot? Thank you in advance, Djordje
The final design was the result of a lot of trial and error. I wonder if it would be possible to model the system to better understand the sound wave interactions so that an understanding of why the various baffle lengths impact the response. If only sound waves could be doped with ink like fluids can to track their vectors, diffractions and even interactions. In any event, it seems evident there is a lot of complicated interactions that these simple baffles are hiding.
Would putting No Rez on the front of the baffle help make the baffle disappear? I've never seen that done, but often wondered how it would affect reflections off the baffle.
Super. Really appreciating these videos. I'd love for you to share in one of these episodes, what you like/don't like or pros/cons between the box kits vs open kits you sell. Both subjective and objective.
hi. i can see you use the bg tweeter whuch is shooting from both sides....uf i use a tweeter with a back cup does the open baffle idea steel stands or is it loosing the whole effect...and if so do i steel need the cut in the 2 inch side ? bc the tweeter is shooting only forwerd.....thx a lot man🤔
Height is not a problem it's the size and width of the baffle that is a problem. Surface reflections and edge diffractions are significant problems with those.
Hi Danny I have a question a little off topic, I am interested in the X-Voce and how it would be affected if it is placed right under a flat screen TV with the front flush with the screen?
I’m new to your channel, so this may have been asked many times before but... I’m curious what you think about magnepan style quasi ribbons vs the cone drivers you’re using for mids, as well as the neo tweeter. It seems the planar nature reduces interference between the front and back waves, though I’m guessing imperfectly. I wonder what wings might do on something like the LRS.
@@dannyrichie9743 I guess the short of what I'm asking is why you choose cone drivers instead. Apples and oranges are still dipole open baffle fruit, so I'm trying to understand the choices made.
That said, I've seen your line source vids with new record day, and that's all neo drivers for highs and mids, so it seems you do use those. I'm a new Magnepan user and audiophile newb. Thinking about building my own bookshelf planar magnetic speakers for fun.
@@aweidenhammer The line of woofers will move more air and play down a lot lower. It makes drums hits and such sound very real. The all planar magnetic drivers keep a narrow baffle width and offer high sensitivity. So imaging is much greater than a Maggie and the sweet spot is much larger. Plus you can drive them with low wattage amplifiers.
So is the optimal set up of a pair of these open baffle speakers 2 units that are identical, or are they mirror images of each other? Also, if mirror images, does the short sidewall go in the middle or to the outside?
Interesting Are you referring to quasi screen wall or baffle wall flush mounting? Something akin to studio flush mounting? Such approaches solve problems that SBIR creates, also gains are had in dynamic output capability. But like anything with loudspeakers/acoustics, it's all an exercise in compromise. Sacrifices in diffraction include imaging and soundstage depth ... but those are oftentimes deemed less important in HT or studios.
@@FOH3663 - scroll through the pictures of the QSC RSC-112 Speaker. Specifically, the RBK-12 baffle wing kit. www.qsc.com/cinema/products/loudspeakers/reference-monitor-system/rsc-112/
