Shapeways? I don't know anything about their resin printers. The sintered powder nylon is superior in about every way, except very smooth surface finish. The build volume is pretty large since all the machines are industrial units, there are no hobbyist sintered nylon machines.
I haven't tried DE250 of course (have barely tried DNA360 very much), but from previous projects they seem to be drop-ins. Same delay offset, very similar frequency responses. (except all the DNA360s I've seen have been somewhat smoother than any of the DE250s I've measured -- though I've only worked with qty=4 DE250, so maybe not too conclusive there!).
I found the two drivers not to be significantly different. I got a better price on the DE250 so I just stuck with it. There has been a change in the DE250 over the years so one has to be careful of the vintage of the drivers being compared. A Chinese made diaphragm used to drop into a DE250, but they don't anymore.
Bill, in your injection molding discussion which Erich, did he mention what the up front manufacturing cost would be for something the size of your waveguide? It seems like if push came to shove and the 3D printing route was too cost prohibitive, perhaps an injection mold and initial run could be crowdfunded, leaving just the driver mounts for 3D printing. DIYers would still have to get their hands dirty with gluing, drilling and filing.
I know the SEOS waveguides have a tramp stamp on their backside ("SEOS") maybe we could get some registers for driver mount locations, drill holes, etc.
I know the SEOS waveguides have a tramp stamp on their backside ("SEOS") maybe we could get some registers for driver mount locations, drill holes, etc.
Last edited:
Hi Brinkman,
We weren't thinking about doing an injection molded version of this horn, it is just too big to be affordable (on a hobby basis and as a molded part) and I don't see any way the woofer ports and ducts could be done at all. The injection mold idea was for a horn "stub" that would be just large enough and detailed enough for the tweeter driver and one or two midranges (either or both types of drivers could be used). It would have tabs then that plywood sections could be bolted onto the stub to make the overall horn as large as wanted (anywhere from 20" to 72" would likely be doable with a stub like that). Woofers could be ported as needed to make it work into the low-midrange or upper bass range. I sort of doubt this will ever happen, it would still be expensive to get a mold made (I don't know a numerical cost figure, but something in the range of a small car). Because of the geometry of a horn, the user would still have to cut angled panels, so more work and calculation than most kit builders would want to do even if they have the tools. So there wouldn't likely be very many people wanting to get into it.
Add the complications of whatever in hell the Danley Synergy patent means (as opposed to the Unity patent which seems to be the same?), and the appeal for putting money into it gets thin. Of course, the stub could be sold as just a general mid or HF horn part (could be used for basic horns, just seal off the un-needed apertures). But not too much demand for just that -- the kit buyers like sure-thing, already worked out, zero risk purchases, except for those few of us that like to make one-of-a-kind projects.
We weren't thinking about doing an injection molded version of this horn, it is just too big to be affordable (on a hobby basis and as a molded part) and I don't see any way the woofer ports and ducts could be done at all. The injection mold idea was for a horn "stub" that would be just large enough and detailed enough for the tweeter driver and one or two midranges (either or both types of drivers could be used). It would have tabs then that plywood sections could be bolted onto the stub to make the overall horn as large as wanted (anywhere from 20" to 72" would likely be doable with a stub like that). Woofers could be ported as needed to make it work into the low-midrange or upper bass range. I sort of doubt this will ever happen, it would still be expensive to get a mold made (I don't know a numerical cost figure, but something in the range of a small car). Because of the geometry of a horn, the user would still have to cut angled panels, so more work and calculation than most kit builders would want to do even if they have the tools. So there wouldn't likely be very many people wanting to get into it.
Add the complications of whatever in hell the Danley Synergy patent means (as opposed to the Unity patent which seems to be the same?), and the appeal for putting money into it gets thin. Of course, the stub could be sold as just a general mid or HF horn part (could be used for basic horns, just seal off the un-needed apertures). But not too much demand for just that -- the kit buyers like sure-thing, already worked out, zero risk purchases, except for those few of us that like to make one-of-a-kind projects.
Last edited:
Full plans, without all the preludes are now at
3D printed 3-way Unity waveguide home audio speaker
Thanks!
3D printed 3-way Unity waveguide home audio speaker
Thanks!
I was once hired to find a way around the Danley patents and yes the two appear to be the same, although there is a subtle difference. The second seems to be a generalized version of the first. The first mentions the need for specific locations along the device and the second relieves this and is more general as to placements.
My recommendation was that the second was so general that it would be very difficult to impossible to get around, although this vast generality would also IMO make it invalid.
The client was not interested in contesting the patent, so it ended there.
Thus, I agree that the patent issue would be a big problem for a mass produced device. Who is going to take on that issue for the minimal interest (and profits) that would ensue?
Bill, you may even be infringing by making the 3D models available. This is called "inducing to infringe".
Oh the joys of living in a litigious society. Who needs to worry about being right when you have enough money to bury the other person in law suits.
Tom Danley himself has given Bill the go ahead before to share his designs so one could only hope they don't feel the need to do any different this time.
Patent worry
You should not care about synergy patent. Renkus-Heinz build the same speaker. I saw it at a show in Copenhagen in the mid nineties. There used to be drawings of it on their web site. Maybe Tom Daley worked for Renkus-Heinz, I dont know, but there is no doubt in my mind that his horns are based upon their design.
Be happy! Thorsten Larsen
You should not care about synergy patent. Renkus-Heinz build the same speaker. I saw it at a show in Copenhagen in the mid nineties. There used to be drawings of it on their web site. Maybe Tom Daley worked for Renkus-Heinz, I dont know, but there is no doubt in my mind that his horns are based upon their design.
Be happy! Thorsten Larsen
Tom Danley told this story once on the forum and I love it:
https://www.diyaudio.com/forums/pa-systems/197713-disappointing-stadium-sound-5.html#post2790598
In the 80’s and 90’s I worked for a small NASA contractor called Intersonics. While there I developed a servomotor driven subwoofer that for example Clair bros used for a couple Michal Jackson tours, the U-2 Zoo tour, Garth brooks, Deaf Leopard and a bunch of others. Clair invited me to attend a couple shows to hear what our 16 subs did added to their 60 to 70 S-4 cabinets per side. I still have the tour jacket they gave me at the Micheal Jackson show, it was so cool sitting in the mix box haha.
For the U-2 show, Clair invited the whole company to a local concert shed, a large open sided arena about 90 min from the shop. I was floored to find they gave us a center sky box right in front of the sound system. That single experience crystallized the goal to make very powerful sources that acted much more like a single driver than even most hifi speakers.
About 12 years ago, a friend teased me about a recent trip to measure the acoustics in the Great Pyramid. Faced with the task of coming up with a first product for a new company, the jab was slightly irritating about using a pyramid to make the sound sharper or something. I thought back to an old Synaudcon class I attended, at a time when my world was exclusively below 100Hz. Don explained about conical horns, that they had good pattern control but also had comparatively poor lf loading.
I was thinking about how to use that shape to get constant directivity and wondering about the poor loading when it hit me. The “horn loading” we all think of has an obvious “high pass” corner based on how fast the horn is expanding. In that view, the hf driver connected at the apex of a conical horn will not have good loading because the expansion rate is initially very fast. Further down the horn however, the expansion rate has slowed and I thought what if I coupled suitable mid driver where the expansion was more appropriate for midrange.
If anyone's into those old Art Bell "Coast to Coast" shows, Tom Danley appeared on it a few times talking about the pyramids.
Here’s the link to their [expired] patent for their CoEntrant horn, granted 6-11-1996: patent US5526456A