OK, I understand.
What I wondered was, given that nothing is perfectly rigid, there will be a transit time for exitation applied by the motor to reach the top of the diaphragm. This will be governed by the speed of sound of torsional waves.
There is also the likelihood of a reflected wave travelling back down from the top of the diaphragm (unless of course it has some damping or termination). This is what made me think of NXT or Walsh type operation.
Cheers,
Ed
What I wondered was, given that nothing is perfectly rigid, there will be a transit time for exitation applied by the motor to reach the top of the diaphragm. This will be governed by the speed of sound of torsional waves.
There is also the likelihood of a reflected wave travelling back down from the top of the diaphragm (unless of course it has some damping or termination). This is what made me think of NXT or Walsh type operation.
Cheers,
Ed
Ed:
OK. Thanks for the insight. I'll be doing testing on P4 to investigate those issues.
P4 is going to be pretty, pretty, pretty rigid. So I am hoping those torsional waves will not be an issue. I will be doing things to ameliorate any wee nonlinearities and vibrational things.
You know the basic design itself does a good job of minimizing those type of issues so there will not be a lot of bad things to deal with.
John
OK. Thanks for the insight. I'll be doing testing on P4 to investigate those issues.
P4 is going to be pretty, pretty, pretty rigid. So I am hoping those torsional waves will not be an issue. I will be doing things to ameliorate any wee nonlinearities and vibrational things.
You know the basic design itself does a good job of minimizing those type of issues so there will not be a lot of bad things to deal with.
John
Planot Speakers Plans vrs Kits
I am very interested in getting feedback from this forum about the viability of selling blueprints for the Planot (tm) speaker.
I know, and many have pointed out, that people will copy the blueprints and either give them away or re-sell them. That would not be advantageous to me when I am trying to generate funds for kits and R&D and legal costs.
I had planned on printing the blueprints with an embedded digital watermark that is a serial number unique to that purchaser. When selling to a world wide audience that will be difficult to police. I have had 3,000 visitors on my Website from 73 countries in the last 3 months. I still might do the blueprints but when I look at the number of users vrs registered users I had when I developed shareware then I am more cautions about that approach. What are your thoughts?
A second option is to sell kits. Full kits, which obviously be more difficult and time consuming for me to get to produce, although I am researching that now. Another option would be a partial kit of the metal parts minus magnets and voice coils. The magnets are dependent on voice coil geometry and therefor I can't provide magnets without voice coils. I am researching voice coil manufacturers.
I am making a rough guesstimate that the partial kits for a pair would sell for $2000 w/o shipping. Remember I am not a manufacturer but if I were have pre-orders of 100 orders then the price would be much lower. No, I am not asking for pre-orders at this point but the longer the list of e-mails expressing interest then the more I will be willing to take such risks. At some point I would have to ask for 100% up font. On demand manufacturing. I would not do that until P4 is built and reviewed.
Any and all feed back would be welcome.
Thanks, John
P.S. I am going to have the motors, hopefully, for P4 built in about 5 weeks. P3 is sounding so good it is scary thinking about how good the two P4's will sound. P3 sounds so much better than my "commercial" speakers that I find it hard to tolerate the commercial speakers any more.
I am very interested in getting feedback from this forum about the viability of selling blueprints for the Planot (tm) speaker.
I know, and many have pointed out, that people will copy the blueprints and either give them away or re-sell them. That would not be advantageous to me when I am trying to generate funds for kits and R&D and legal costs.
I had planned on printing the blueprints with an embedded digital watermark that is a serial number unique to that purchaser. When selling to a world wide audience that will be difficult to police. I have had 3,000 visitors on my Website from 73 countries in the last 3 months. I still might do the blueprints but when I look at the number of users vrs registered users I had when I developed shareware then I am more cautions about that approach. What are your thoughts?
A second option is to sell kits. Full kits, which obviously be more difficult and time consuming for me to get to produce, although I am researching that now. Another option would be a partial kit of the metal parts minus magnets and voice coils. The magnets are dependent on voice coil geometry and therefor I can't provide magnets without voice coils. I am researching voice coil manufacturers.
I am making a rough guesstimate that the partial kits for a pair would sell for $2000 w/o shipping. Remember I am not a manufacturer but if I were have pre-orders of 100 orders then the price would be much lower. No, I am not asking for pre-orders at this point but the longer the list of e-mails expressing interest then the more I will be willing to take such risks. At some point I would have to ask for 100% up font. On demand manufacturing. I would not do that until P4 is built and reviewed.
Any and all feed back would be welcome.
Thanks, John
P.S. I am going to have the motors, hopefully, for P4 built in about 5 weeks. P3 is sounding so good it is scary thinking about how good the two P4's will sound. P3 sounds so much better than my "commercial" speakers that I find it hard to tolerate the commercial speakers any more.
Thanks for the update.
I'm really skeptical whether blueprints would sell in significant numbers and at a price that would generate your development funds. As for digital watermarks etc., unless you have the resources available to police your copyright and pursue those in breach, it is of little use in practice. Sorry, I don't mean to sound anything but realistic - I've seen what can happen in other business & commercial/tech situations.
A starter kit would be more attractive and offer something tangible - but of course more work for you. At $2000 for a "partial kit", I suspect the interest would be limited for something so novel and downright counter-intuitive unless it were possible to offer a demonstration. $2000 buys a reasonable amount of commercial 'speaker, and some pretty impressive DIY parts, which is what you would be pitched against.
Again these are just my "knee jerk" reactions and not an in depth consideration. I recognise that your efforts take time and resources, for which you would like to see some reward.
Please keep us updated with progress and test figures 😉 when you get the chance.
Cheers,
Ed
I'm really skeptical whether blueprints would sell in significant numbers and at a price that would generate your development funds. As for digital watermarks etc., unless you have the resources available to police your copyright and pursue those in breach, it is of little use in practice. Sorry, I don't mean to sound anything but realistic - I've seen what can happen in other business & commercial/tech situations.
A starter kit would be more attractive and offer something tangible - but of course more work for you. At $2000 for a "partial kit", I suspect the interest would be limited for something so novel and downright counter-intuitive unless it were possible to offer a demonstration. $2000 buys a reasonable amount of commercial 'speaker, and some pretty impressive DIY parts, which is what you would be pitched against.
Again these are just my "knee jerk" reactions and not an in depth consideration. I recognise that your efforts take time and resources, for which you would like to see some reward.
Please keep us updated with progress and test figures 😉 when you get the chance.
Cheers,
Ed
I think it should be possible to build a simple moving magnet drive that is far away enough from Thomas Danley´s patent, not as linear, but cheap.
Re: Planot Speakers Plans vrs Kits
Unfortunately for you, it seems to me that you have already provided enough information on the various web forums for anyone serious about building a Planot speaker to do so.
$2000 is a bit steep for any DIY loudspeaker, let alone an unknown and incomplete kit. What does one get: several feet of aluminum extrusion cut to size and a couple 4' carbon fibre triangular tubes? The magnets and coils are the hardest part (other than robbing a dead hard disk drive 😉).
I recall reading somewhere (elsewhere?) that you had paid ~$900 for a few minimally machined blocks of aluminum for P4. Might I kindly suggest that you find a more affordable
machine shop.
Why was it that you didn't want to sell complete speakers?
I don't mean to come off as a jerk but you did say....
planot said:
Unfortunately for you, it seems to me that you have already provided enough information on the various web forums for anyone serious about building a Planot speaker to do so.
$2000 is a bit steep for any DIY loudspeaker, let alone an unknown and incomplete kit. What does one get: several feet of aluminum extrusion cut to size and a couple 4' carbon fibre triangular tubes? The magnets and coils are the hardest part (other than robbing a dead hard disk drive 😉).
I recall reading somewhere (elsewhere?) that you had paid ~$900 for a few minimally machined blocks of aluminum for P4. Might I kindly suggest that you find a more affordable
machine shop.
Why was it that you didn't want to sell complete speakers?
I don't mean to come off as a jerk but you did say....
planot,
Make the design open and sell the product. That is what other loudspeaker manufacturers do. Publishing the underlying theory in technical periodicals (like JAES) in fact contributes to going to market. It will prove that the product works on a well-understood and tested principle, and it will show its superiority. If the operating principle is patented, there is nothing to worry about other manufacturers stealing your invention. DIY-ers are not a competition, they do not buy the ready-made speaker, on the other hand laymen can not build one even having the design details. Selling the product en masse for laymen should make you profit.
Make the design open and sell the product. That is what other loudspeaker manufacturers do. Publishing the underlying theory in technical periodicals (like JAES) in fact contributes to going to market. It will prove that the product works on a well-understood and tested principle, and it will show its superiority. If the operating principle is patented, there is nothing to worry about other manufacturers stealing your invention. DIY-ers are not a competition, they do not buy the ready-made speaker, on the other hand laymen can not build one even having the design details. Selling the product en masse for laymen should make you profit.
I consider building a planot and I am interested in your opinions about the following two alternatives.
First the moving magnet version:
A magnet rod is glued to the bottom of a balsawood bar, surrounded by the c-shaped silicon-iron core of the voice coil. My doubt: Is the voice coil inductance low enough and the MOI of the magnet low enough for delivering the heights?
Second the moving coil version:
Two thin channels are drilled into the bar and the voice coil is thread through them. A closed magnetic circuit with two large neodymium blocks surrounds the whole bar. My doubt: Is 0.4 Tesla high enough for a reasonable Qe?
I believe to have solved the suspension problem and I will use no spindle.
Do you think any of the two versions can work?
First the moving magnet version:
A magnet rod is glued to the bottom of a balsawood bar, surrounded by the c-shaped silicon-iron core of the voice coil. My doubt: Is the voice coil inductance low enough and the MOI of the magnet low enough for delivering the heights?
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Second the moving coil version:
Two thin channels are drilled into the bar and the voice coil is thread through them. A closed magnetic circuit with two large neodymium blocks surrounds the whole bar. My doubt: Is 0.4 Tesla high enough for a reasonable Qe?
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
I believe to have solved the suspension problem and I will use no spindle.
Do you think any of the two versions can work?
el`ol, that is interesting.
Your moving coil version is something like the implementation of a meter movement. Given that 360° rotation is not required, you could also include a pole, supported by some kind of "spider" at the center of the coil to reduce the gap and improve drive efficiency.
Removal of the bearing is also a good point, I also have some ideas how this might be implemented, and impart further additional benefits to the design.
Ed
Your moving coil version is something like the implementation of a meter movement. Given that 360° rotation is not required, you could also include a pole, supported by some kind of "spider" at the center of the coil to reduce the gap and improve drive efficiency.
Removal of the bearing is also a good point, I also have some ideas how this might be implemented, and impart further additional benefits to the design.
Ed
Update to Planot (tm) Web site & Public questions...
I have a new picture on the home page of the progress with the planot motor. There also new testimonials on the testimonial page. I have finished the "experimental license" document. I am close to completing the finished motors and the final blueprints for them. Next I will finish the new diaphragms.
This process is taking a long time mainly the result of my perfectionism and events outside of my control. I have had great difficulty finding qualified and professional machinists to fabricate parts. I have a working relationship with a good machinist now.
I have found a source for magnets and am still working on a source for voice coils.
I am think most people would want to purchase at least the parts for "whole motors" and not have to provide their own magnets and voice coils.
The frames and bases would not be terribly difficult to make for the purchaser.
What do you think about the diaphragms? Would most people definitely want to buy the diaphragms kit?
I am trying to strike a mid ground between cost and ease of construction.
How much would you pay for a complete motor kit?
How much would you pay for a complete diaphragm kit?
The more responses I get, both private and public, the better I will be able to gauge your expectations.
John
I have a new picture on the home page of the progress with the planot motor. There also new testimonials on the testimonial page. I have finished the "experimental license" document. I am close to completing the finished motors and the final blueprints for them. Next I will finish the new diaphragms.
This process is taking a long time mainly the result of my perfectionism and events outside of my control. I have had great difficulty finding qualified and professional machinists to fabricate parts. I have a working relationship with a good machinist now.
I have found a source for magnets and am still working on a source for voice coils.
I am think most people would want to purchase at least the parts for "whole motors" and not have to provide their own magnets and voice coils.
The frames and bases would not be terribly difficult to make for the purchaser.
What do you think about the diaphragms? Would most people definitely want to buy the diaphragms kit?
I am trying to strike a mid ground between cost and ease of construction.
How much would you pay for a complete motor kit?
How much would you pay for a complete diaphragm kit?
The more responses I get, both private and public, the better I will be able to gauge your expectations.
John
Attachments
friendly advice (really)
I think these two statements sort of demonstrate a good point: the DIY community is an incredible resource that you are not yet availing yourself of fully.
I understand you not wanting to give any potential commercial competitors a head start on making money from your bright ideas. Hopefully, the patent you applied for will be the first of many granted to you, and you be able to get as rich as you'd like from your innovations.
It appears that you got off on the wrong foot in here, and may have temporarily alienated some potential allies.
It also appears that you have no idea how much everyone here is hoping that you really have made a breakthrough similar to what you are describing.
Looking for sources for magnets and incredible metalworking skills? Wander over and see the guys in the ribbon threads. A source for voice coils? No better group of people than here.
These people WANT to see a radical innovation that has the potential to be the next ESL, the next plasma tweeter, fan subwoofer, horn, ribbon. It seems to me that they don't yet care if YOU get credit for it, or famous, or rich, but believe me, they are willing to read a lot of conjecture to find the rare pieces that might just work.
They are willing to help people of good will, and are on the edge of their seats waiting to see the results of innovation--the graphs, the pictures, the crazy subjective descriptions after listening tests.
We are all here to learn and teach.
If you are already super well-connected to craftsmen and manufacturers and designers and engineers (and reviewers, and marketing and PR people) AND you have a huge wallet full of cash, then maybe you don't need these guys, and maybe you are well on your way to audiophile commercial success. (I am guessing that's not yet completely the case, if finding a source for magnets was a challenge -- are easy to get if you are EITHER rich or well connected.)
I believe that if your idea is truly as good as you seem to think it is, you will be able to make valuable friends here, and still make a huge pile of money. And don't think for a second that the DIY community is going to be parasitic on your success.
If you'd like to see a good example of a guy that is holding some secrets away from theft/exploitation, but still being a great team player, search for some posts from Tom Danley (and MANY others, but he was the first I thought of that is holding a few proprietary cards close to his chest while still helping nearly everyone that asks).
If you don't form a good relationship with some people that really know what they are talking about, you may find your commercial venture lasts about as long as a carnival goldfish. You can find people to sell you magnets and aluminum and patent searches. I swear you are gonna get ripped off though, and end up with engineering specs that call for "infinitely rigid, massless unobtanium" and and someone willing to sell it to you.
We have all heard the miracle claims that you have made, (including a few that seemed to contradict each other) but we have also heard many "world's best loudspeaker" claims. If we merely believed all of the testimonials presented to us, we would have joined every church that tried to recruit us.
So, this is a friendly warning. You need a symbiotic relationship with some people that really know what they are talking about. Otherwise, you are going to be kicking yourself someday when you realize that you have made a mistake in your calculations and now require grille cloth with a 12db gain or something.
To quote the Ghostbusters, "we're ready to believe you." But curiosity and the anticipation are killing us. Throw us a bone, or disbelief starts to set in.
When you assert that you have already said enough for someone to replicate your design and we still don't see the miracle, then you lose us a little bit. Now is the time to get the tough questions answered--at least for YOU to know you can answer them, even if you can't share so much yet.
Maybe you trust one guy, and he finds an error in your math. Another guy might see a physics problem, or a materials problem.
Worst case, is that someone will say "Oh, that's just like (some prior art) and it doesn't work." But it's better to hear that now and overcome the necessary obstacles, than to find out after you have a warehouse full of titanium, kapton and magnets.
I believe you may be on to something truly unique -- even if it's only the "no back wave" bit, but you are only going to be disappointed if you try to be an ivory tower Tesla about it.
I seriously hope you have stumbled upon something as fundamental as the wheel or fire here, or as unbelievable as anti-gravity boots or perpetual motion. I hope it is as remarkable as you seem to think it is.
If you want to move fast and capitalize on your invention and get out in front of the market, I highly recommend that you engage in some peer review.
planot said:
I think these two statements sort of demonstrate a good point: the DIY community is an incredible resource that you are not yet availing yourself of fully.
I understand you not wanting to give any potential commercial competitors a head start on making money from your bright ideas. Hopefully, the patent you applied for will be the first of many granted to you, and you be able to get as rich as you'd like from your innovations.
It appears that you got off on the wrong foot in here, and may have temporarily alienated some potential allies.
It also appears that you have no idea how much everyone here is hoping that you really have made a breakthrough similar to what you are describing.
Looking for sources for magnets and incredible metalworking skills? Wander over and see the guys in the ribbon threads. A source for voice coils? No better group of people than here.
These people WANT to see a radical innovation that has the potential to be the next ESL, the next plasma tweeter, fan subwoofer, horn, ribbon. It seems to me that they don't yet care if YOU get credit for it, or famous, or rich, but believe me, they are willing to read a lot of conjecture to find the rare pieces that might just work.
They are willing to help people of good will, and are on the edge of their seats waiting to see the results of innovation--the graphs, the pictures, the crazy subjective descriptions after listening tests.
We are all here to learn and teach.
If you are already super well-connected to craftsmen and manufacturers and designers and engineers (and reviewers, and marketing and PR people) AND you have a huge wallet full of cash, then maybe you don't need these guys, and maybe you are well on your way to audiophile commercial success. (I am guessing that's not yet completely the case, if finding a source for magnets was a challenge -- are easy to get if you are EITHER rich or well connected.)
I believe that if your idea is truly as good as you seem to think it is, you will be able to make valuable friends here, and still make a huge pile of money. And don't think for a second that the DIY community is going to be parasitic on your success.
If you'd like to see a good example of a guy that is holding some secrets away from theft/exploitation, but still being a great team player, search for some posts from Tom Danley (and MANY others, but he was the first I thought of that is holding a few proprietary cards close to his chest while still helping nearly everyone that asks).
If you don't form a good relationship with some people that really know what they are talking about, you may find your commercial venture lasts about as long as a carnival goldfish. You can find people to sell you magnets and aluminum and patent searches. I swear you are gonna get ripped off though, and end up with engineering specs that call for "infinitely rigid, massless unobtanium" and and someone willing to sell it to you.
We have all heard the miracle claims that you have made, (including a few that seemed to contradict each other) but we have also heard many "world's best loudspeaker" claims. If we merely believed all of the testimonials presented to us, we would have joined every church that tried to recruit us.
So, this is a friendly warning. You need a symbiotic relationship with some people that really know what they are talking about. Otherwise, you are going to be kicking yourself someday when you realize that you have made a mistake in your calculations and now require grille cloth with a 12db gain or something.
To quote the Ghostbusters, "we're ready to believe you." But curiosity and the anticipation are killing us. Throw us a bone, or disbelief starts to set in.
When you assert that you have already said enough for someone to replicate your design and we still don't see the miracle, then you lose us a little bit. Now is the time to get the tough questions answered--at least for YOU to know you can answer them, even if you can't share so much yet.
Maybe you trust one guy, and he finds an error in your math. Another guy might see a physics problem, or a materials problem.
Worst case, is that someone will say "Oh, that's just like (some prior art) and it doesn't work." But it's better to hear that now and overcome the necessary obstacles, than to find out after you have a warehouse full of titanium, kapton and magnets.
I believe you may be on to something truly unique -- even if it's only the "no back wave" bit, but you are only going to be disappointed if you try to be an ivory tower Tesla about it.
I seriously hope you have stumbled upon something as fundamental as the wheel or fire here, or as unbelievable as anti-gravity boots or perpetual motion. I hope it is as remarkable as you seem to think it is.
If you want to move fast and capitalize on your invention and get out in front of the market, I highly recommend that you engage in some peer review.
Read the description from website and did not get just one thing:
- what is the task of homing magnets on the back side diafragm together with bigger homing magnet fixed close to them?
- what is the task of homing magnets on the back side diafragm together with bigger homing magnet fixed close to them?
Charcoal said:
Same as the spider for a conventional driver. But I have my doubts wheter this is as linear as a mechanical solution. I will neither use a homing magnet nor a spindle in my Planot clone.
Spider - that was what I thought also when looked at picture.
The second thaought was like yours: how linera it is comparing to mechenical?
Its also interesting how the cumulative spectrum and impulse response will compare to usual drivers...
The second thaought was like yours: how linera it is comparing to mechenical?
Its also interesting how the cumulative spectrum and impulse response will compare to usual drivers...
Charcoal said:
I intend to use a 1 cm high cross with 10 cm diameter made of 1 mm abachi that rests on four pads of flexible acrylic. One at each end, mounted into sawed slots with non-elastic glue. Better suggestions?
Not sure where to place the coil, yet.
Have emailed John at Planot. P4 is nearly ready - there will be 2 of them with alternate diaphragms until the carbon fibre one's are ready.
I was also told that he compared P3 at a friend's house recently(avantegard horns) and they both agreed that the P3 ''beat the heck out of the avant in coherence, imaging and timbre''.
I asked for a SPL at 1 watt/1metre but got no answer. This worries me some what because low-medium efficiency doesn't cut it for me anymore - especially with low power valve amplification.
I am in no way associated with john, but thought I would pass on this information as the latest point in progress.
I was also told that he compared P3 at a friend's house recently(avantegard horns) and they both agreed that the P3 ''beat the heck out of the avant in coherence, imaging and timbre''.
I asked for a SPL at 1 watt/1metre but got no answer. This worries me some what because low-medium efficiency doesn't cut it for me anymore - especially with low power valve amplification.
I am in no way associated with john, but thought I would pass on this information as the latest point in progress.
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