Dude, you're super over thinking this. Do the Anarchy tapped horns, they're small and pretty good. I've got a pair acting as stands in my bedroom system. Danley does not care if you sell yours when you're done. Diy sound group even sold a flat pack cabinet for those things for a while, with Danleys blessing.
I'm pretty sure the patent was granted long before DIYSG ever sold their first flat pack so that response doesn't make a whole lot of sense. Even if it wasn't granted at the time (I'm pretty sure it was) the tapped horn concept was ALWAYS patent pending since the moment it was introduced, which means hands off for commercial profit until/unless patent is denied. DIYSG was producing them for sale to make a profit so he probably got a cease and desist.
DIYSG is not nearly as philanthropical as he pretends to be. The guy doesn't know much if anything about audio, he gets his designs for free from the community (SEOS horn and all speaker designs), he makes a bloody fortune selling stuff at WAY over market pricing and he pretends he's doing community service and not making profit. In fact the SEOS horns only cost him $14 to make (the 12 inch version) but he still charges $28. The extra $14 was supposed to pay for tooling for the first batch. But he continues to charge $28 and he'll never change that (except to raise the price at some point). He's making a fortune, he's not doing this to help people or for the good of his health.
I would not be surprised at all if Danley stepped on his toes and told him to back off and I wouldn't blame Danley for it at all. I'm pretty sure he never asked permission in the first place - the weird reply you received seems to support that.
The Anarchy tapped horns plans are freely available as are a few dozen other tapped horn plans including the TH_SPUD, which is better than most.
You don't need a flat pack. If you are still worried about the patent infringement thing do a transmission line or a front loaded horn.
DIYSG is not nearly as philanthropical as he pretends to be. The guy doesn't know much if anything about audio, he gets his designs for free from the community (SEOS horn and all speaker designs), he makes a bloody fortune selling stuff at WAY over market pricing and he pretends he's doing community service and not making profit. In fact the SEOS horns only cost him $14 to make (the 12 inch version) but he still charges $28. The extra $14 was supposed to pay for tooling for the first batch. But he continues to charge $28 and he'll never change that (except to raise the price at some point). He's making a fortune, he's not doing this to help people or for the good of his health.
I would not be surprised at all if Danley stepped on his toes and told him to back off and I wouldn't blame Danley for it at all. I'm pretty sure he never asked permission in the first place - the weird reply you received seems to support that.
The Anarchy tapped horns plans are freely available as are a few dozen other tapped horn plans including the TH_SPUD, which is better than most.
You don't need a flat pack. If you are still worried about the patent infringement thing do a transmission line or a front loaded horn.
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I actually built a version of the TH-Spud a number of years ago (7-8) . I ended up giving the cabinet to my neighbor (without the drivers) and he used it to train his horses to step up with it. It was quite good. I also built a pair of 40 hz TH that my brother in law uses as subs for his garage band. He likes them a lot. I have the wood cut and drivers for another pair of 40 hz THs should I decide to build them.
So, yes, I understand What THs can do, and I am aware of building patented devices for investigative purposes. I built mine before Danley's patent was granted in 2013.
What is our purpose here, to create cookie cutter systems? Or to extend the art form and develop innovative new ways of making noise? Or at least new ways of putting together different technologies that yield unique results.
So, yes, I understand What THs can do, and I am aware of building patented devices for investigative purposes. I built mine before Danley's patent was granted in 2013.
What is our purpose here, to create cookie cutter systems? Or to extend the art form and develop innovative new ways of making noise? Or at least new ways of putting together different technologies that yield unique results.
I don't understand your willingness to build a patent pending project but not a patented project. If there was any real difference it would be open season (diy and commercial) on patent pending IP. I'm fairly sure that once the patent is granted the patent holder can sue everyone that used the idea while it was pending. I don't see any difference other than the fact that patent pending IP might not actually be granted a patent. This distinction between patent pending IP being fair game but patented IP being off limits makes no sense at all to me.
I can't speak for anyone else but my purpose here is to collect and share information.
My purpose in audio studies is mainly to understand enclosure design, that's always been my main focus and why I got into this.
In this endeavor I have been quite successful. I can understand designs just by looking at them and have a fair idea what they are going to do without seeing measurements or hearing them. I can design just about anything you can imagine.
But there's not much new under the sun. I haven't been able to extend the "art form" (theory) as of yet unless you count personal designs and twists on well known theory. I'm not sure if you are saying you want to do something new or not, but tapped horns and dipole and all of it's variants are nothing new.
I can't speak for anyone else but my purpose here is to collect and share information.
My purpose in audio studies is mainly to understand enclosure design, that's always been my main focus and why I got into this.
In this endeavor I have been quite successful. I can understand designs just by looking at them and have a fair idea what they are going to do without seeing measurements or hearing them. I can design just about anything you can imagine.
But there's not much new under the sun. I haven't been able to extend the "art form" (theory) as of yet unless you count personal designs and twists on well known theory. I'm not sure if you are saying you want to do something new or not, but tapped horns and dipole and all of it's variants are nothing new.
First, not all items which are "patent pending" are issued patents.
The TH SPUD I built for investigative purposes, and after experimenting (playing around) I effectively destroyed it. The other pair were again built before the patent was granted. The last pair, I have sitting in my garage un-built partly because of the problem with the patent.
So as to not lose my original purpose in the noise, I will create a new post with some other ideas that I have about what I am trying to accomplish.
The TH SPUD I built for investigative purposes, and after experimenting (playing around) I effectively destroyed it. The other pair were again built before the patent was granted. The last pair, I have sitting in my garage un-built partly because of the problem with the patent.
So as to not lose my original purpose in the noise, I will create a new post with some other ideas that I have about what I am trying to accomplish.
I have been out of town for a few days and have had time to think other crazy thoughts that may have some or no merit.
The first is regarding Ripoles. They seem to always have two woofers opposed. I suspect this cancels vibrations in the cabinet. Say that I wanted to use a single 15" driver with two slots both the same frontal area, 1/3 the SD, say.
Would the loss of efficiency be linear (1/2 two drivers), or would there be other artifacts that I would need to control for?
Basically my goal is to make a bass cabinet that is L shaped with a base of no more than 20" and a height of no more than 30" that will have a shelf no more than 10" square.
The first is regarding Ripoles. They seem to always have two woofers opposed. I suspect this cancels vibrations in the cabinet. Say that I wanted to use a single 15" driver with two slots both the same frontal area, 1/3 the SD, say.
Would the loss of efficiency be linear (1/2 two drivers), or would there be other artifacts that I would need to control for?
Basically my goal is to make a bass cabinet that is L shaped with a base of no more than 20" and a height of no more than 30" that will have a shelf no more than 10" square.
Attachments
Not sure what you are saying here but there is no exemption for investigative purposes, not as far as this discussion goes anyway.
Here's a very pointed quote -
That quote comes from a neat paper that identifies a lot of problems in the patent system.
http://lsr.nellco.org/cgi/viewcontent.cgi?article=1272&context=nyu_lewp
The "fair use" argument is a figment of copyright law, not patent law.
So what are the "research exemptions"?
First you have the "safe harbor" exemption which is mostly about drugs and not allowing patents to cause unnecessary deaths.
Then there's the "Common law research exemption", which would seem to apply here but it doesn't. All this exemption allows for is "amusement, to satisfy idle curiosity, or for strictly philosophical inquiry."
There's plenty of documented information on all aspects of tapped horns which leaves no room for strictly philosophical inquiry. As far as amusement and idle curiosity, that's far different than making things that are fully functional for the purpose of using them.
US patent law makes no "fair use" exemption for diy'ers building tapped horns for their own systems.
Research exemption - Wikipedia
But the thing is that nobody cares, as long as it's JUST diy'ers building their own subs and not companies like DIYSG blatantly ignoring the patent and producing (literally) tons of product for the express purpose of profit.
I think you are going to need to get a simulator as I suggested a few days ago. I doubt anyone is going to spend any significant amount of time discussing a bass black hole like a ripole.
To be blunt, OB has no place at subwoofer frequencies. IMO of course. There are no advantages and a few very significant disadvantages.
So get a simulator or build a documented project like Pass' OB system and revel in how little sound OBs make at low frequencies.
LOL, this is remarkably similar to saying it's only a crime if you get caught. "It's only patent infringement if the patent is granted" is not a moral or legal defense, hence my confusion over your willingness to build patent pending IP but not patented IP. It makes no sense.
This is not a thread about;
1) Patents.
2) Tapped Horns.
As I tried to redirect the thread above, it is about merging the aesthetics of a small frontal area with a woofer section of a multi way open baffle (OB) system. The reason for exploring OB woofers is because the rest of the system is OB, and many folks claim that non-OB systems do not integrate well with OB systems.
If you have nothing to add to this discussion, I'm sure there are other places where you can debate patents all day long.
I am somewhat familiar with problems of OB/dipole systems, however having recently completed a pair of GR Research/Rythmik Audio "W" based 12" OB subs, I know that building an OB woofer section is possible, and they play well to reasonably low frequencies. However the pair of them cost $1,500 in drivers & amps alone, so I am looking for a lower cost and physically smaller alternative.
My goal is a woofer section that will reproduce as low into the 20's as possible with an upper end in the 80-100hz range, and will be as "musical," "fast" as the rest of the OB system I am putting together. I am willing to use separate amplification for the woofer section in order to match efficiency, as well as either dsp or a parametric eq for the woofer section only.
One other design constraint is the system must appear as a single load to the amplifier. In other words if separate amplification is used it must have speaker level in.
1) Patents.
2) Tapped Horns.
As I tried to redirect the thread above, it is about merging the aesthetics of a small frontal area with a woofer section of a multi way open baffle (OB) system. The reason for exploring OB woofers is because the rest of the system is OB, and many folks claim that non-OB systems do not integrate well with OB systems.
If you have nothing to add to this discussion, I'm sure there are other places where you can debate patents all day long.
I am somewhat familiar with problems of OB/dipole systems, however having recently completed a pair of GR Research/Rythmik Audio "W" based 12" OB subs, I know that building an OB woofer section is possible, and they play well to reasonably low frequencies. However the pair of them cost $1,500 in drivers & amps alone, so I am looking for a lower cost and physically smaller alternative.
My goal is a woofer section that will reproduce as low into the 20's as possible with an upper end in the 80-100hz range, and will be as "musical," "fast" as the rest of the OB system I am putting together. I am willing to use separate amplification for the woofer section in order to match efficiency, as well as either dsp or a parametric eq for the woofer section only.
One other design constraint is the system must appear as a single load to the amplifier. In other words if separate amplification is used it must have speaker level in.
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I have plenty to add but I don't think you want to hear it.
Dipoles (all variants) drop at a rate of 18 db/oct (IIRC) below the dipole peak (the first big peak) unless you have a driver with appropriately high qts and fs a bit below the low knee frequency to counter the rolloff.
With a narrow frontal face the dipole peak is going to be up somewhere around 1 khz, and then below 1 khz you will have a rolloff of 18 db/oct.
So at 20 hz you will be down maybe close to 100 db compared to 1 khz. That is simply not feasible from any standpoint. Whether you boost the lows or kill the highs or both that's simply not a feasible sensitivity to work with.
As you have been told a few times you will need either a very large flat baffle or a very long U or H baffle to get anywhere near 20 hz with OB. OB has no room gain so even a 4 inch woofer in a sealed box is going to put out more 20 hz than a large OB.
MJK found the right balance, 40 hz is about the practical lower limit for OB for a bunch of different reasons. Striving to hit anywhere near 20 hz with OB is a waste of time and money.
You really need to get a simulator. The reality of the situation seems to elude you still. Dipole cancellation at anywhere near 20 hz is going to be a massive suckout bass black hole and nothing can fix it - not high q drivers, not eq, not even floor to ceiling arrays of large drivers.
Dipoles (all variants) drop at a rate of 18 db/oct (IIRC) below the dipole peak (the first big peak) unless you have a driver with appropriately high qts and fs a bit below the low knee frequency to counter the rolloff.
With a narrow frontal face the dipole peak is going to be up somewhere around 1 khz, and then below 1 khz you will have a rolloff of 18 db/oct.
So at 20 hz you will be down maybe close to 100 db compared to 1 khz. That is simply not feasible from any standpoint. Whether you boost the lows or kill the highs or both that's simply not a feasible sensitivity to work with.
As you have been told a few times you will need either a very large flat baffle or a very long U or H baffle to get anywhere near 20 hz with OB. OB has no room gain so even a 4 inch woofer in a sealed box is going to put out more 20 hz than a large OB.
MJK found the right balance, 40 hz is about the practical lower limit for OB for a bunch of different reasons. Striving to hit anywhere near 20 hz with OB is a waste of time and money.
You really need to get a simulator. The reality of the situation seems to elude you still. Dipole cancellation at anywhere near 20 hz is going to be a massive suckout bass black hole and nothing can fix it - not high q drivers, not eq, not even floor to ceiling arrays of large drivers.
Remember, the baffle width controls the dipole peak frequency, this is important because below the dipole peak frequency you get the dipole rolloff. This is why you sometimes see extremely large baffles for OB. The lower you can push that peak the later the rolloff will start.
A wide baffle is also synonymous with a deep U or H frame.
Your design goal of a very narrow frontal face equates to a very narrow baffle. Your design goal of hitting down to near 20 hz complicates things further.
Your combined design goals leave no room for a feasible application - sensitivity is going to be shockingly low. That's just the way it is, there's no way around it. It simply is not going to work.
A wide baffle is also synonymous with a deep U or H frame.
Your design goal of a very narrow frontal face equates to a very narrow baffle. Your design goal of hitting down to near 20 hz complicates things further.
Your combined design goals leave no room for a feasible application - sensitivity is going to be shockingly low. That's just the way it is, there's no way around it. It simply is not going to work.
My GR Research 12" OB "W" system yields < 20hz measured in room response to reasonably high levels. If it can be done with 2 - 12" woofers, why not 4 - 8", or some other configuration.
If not Dipole, what else should I investigate. Heck why not 4 "tuned pipes" or band pass enclosures with one or two 8" drivers covering a specific bandwidth.
If not Dipole, what else should I investigate. Heck why not 4 "tuned pipes" or band pass enclosures with one or two 8" drivers covering a specific bandwidth.
Your GR W baffle is fairly large compared to the tiny designs you have been contemplating. It also has some depth to it, which effectively increases the baffle size. And the woofers are fairly high excursion compared to the drivers we have been discussing.
Even so, what is the max spl at 20 hz with your GR OB? I'd bet it's absurdly low for a couple of 12 inch woofers with decent xmax.
I've mentioned transmission lines at least a couple of times now, they are "tuned pipes". You can also investigate literally everything except OB - sealed, ported, tl, bandpass, front loaded horn, etc. Those will all give vastly more bass at 20 hz than any type of OB. And they will all blend with your OB mains just fine.
Even so, what is the max spl at 20 hz with your GR OB? I'd bet it's absurdly low for a couple of 12 inch woofers with decent xmax.
I've mentioned transmission lines at least a couple of times now, they are "tuned pipes". You can also investigate literally everything except OB - sealed, ported, tl, bandpass, front loaded horn, etc. Those will all give vastly more bass at 20 hz than any type of OB. And they will all blend with your OB mains just fine.
So, If I use a group of 6"-8" drivers with the equivalent SD x Xmax, to the two 12" GR woofers, place them in a cabinet with at least the same depth, it should yield similar performance?
The QTS is rather low in the GR drivers, but it is my understanding that they overcome that with the servo, and tweaking the amp.
The QTS is rather low in the GR drivers, but it is my understanding that they overcome that with the servo, and tweaking the amp.
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