Pixel there are two things at play here. One is that it's always interesting to see if and how and why the theory matches up with the practice. It's quite satisfying to predict something in the math and then build it and confirm the sums.
The other thing is that the goals for big companies are almost always different to those of the individual tinkerer. Big companies with millions of investment dollars at their disposal have to show high-certainty, positive returns to investors and shareholders. This sometimes leaves high-risk-but-interesting paths unexplored.
So yes, carbon-fibre/Nomex, space-age panels are possibly the best-performing materials in almost all respects, and they almost guarantee a good end-product. But I wonder if the cost/performance ratio is really as that much higher than Alu foil or paper and EPS etc. I can't say yet if the numbers are conclusive.
bye thank you
in principle you are right about everything but considering the application for professional use and time and money to buy all the possible materials over the enormous time to carry out the tests I do not think it is worth experimenting with materials already enormously tried and tested, it could be It is useful to start again from the point that tectonic has reached and maybe try to improve that, as long as the system can be improved.As far as costs are concerned, a panel identical or almost identical to the tectonic one costs 90 euros. considering the panel the structure that supports the exciters and the good endings with dsp we must ask ourselves if it is worthwhile when there are traditional systems that are good and cost even less.In practice, in the end, the cost is not the puntyo in favor of this system but it should be the quality, I have never heard tectonic because in Europe they do not exist they are not sold, so I still ask myself the question of the per which has never been successful both as home speakers and for professional applications
Pixel I have worked as designer in large R&D departments, and I can safely say that such departments do not necessarily have an unassailable advantage over an engineer endowed with a bit of common sense who is working alone in his garage. In fact, it's pretty likely that development projects in an R&D division are most likely driven and developed upon the inspiration of exactly such a passionate individual—a product Champion.
The only advantage that such a Champion has is that he has job security and access to test gear. But on the other hand, he's likely hamstrung by red tape, bureaucracy, committees, team opinions and endless paper work. What a lone inventor can accomplish over a weekend will probably take months for a "design team" to perform the same amount of work.
The massive advantage of a big organisation, however, is a sales/marketing department. This is what convinces the buyer of the apparent high quality of the product irrespective of the fact that their product might be extremely second-rate.
Thanks for the reply
it will certainly be true that you say, I know companies just that at a profit, however in the case of "small" companies like tectonic that has decided to undertake a difficult commercial path like dml panels, in a sector like the professional one, it is unthinkable that I believe that they have reached a low level of the market (according to them) to such a state that it would not have been replicated by the dedicated market and perhaps they have probably seen limits that we do not set ourselves.
As einstain said Fantasy is more important than knowledge, because knowledge is limited.
Always bolt the exciter onto a brace with the thread provided on the back of the magnet. It's there for a reason.
If this is done, then the adhesive on the front should be more than sufficient.
Hello Pixel1
My plywood panel have been working for more than one year with the original tape. The exciter is fixed on the back thanks to the provided holes. For my canvas panel, it is a reuse of exciters so I used epoxy glue to the membrane. On the other thread you should find posts from Spedge with wood glue.
Christian
I agree and thought the same when I started experimenting with the plates. Simple answer, cost and effort. The GPS plates I use are very cheap to buy and just slab on some hide glue and shellac and they sound great and are very efficient.
The ready made nomex/CF plates I have seen have quite thick carbon skin, so will probably not be sensitive enough. Perhaps there are places that can make according to order. Making your own is not that easy, but I have started experimenting with it and hope to continue with that this spring. But even so they do cost more than 200 € each to make in material costs, so will more than double the total cost per plate including exciters. I looked around quite a bit and haven't seen any plates comparable to the ones Tectonic use for 90€ each.
I was just surprised during my tests how well GPS plates worked, and realized I could make a system to try out for a reasonable budget, and if it worked out but I want to upgrade to CF composite, I haven't lost much making the plates with GPS initially.
I might found a possible reason that CF plates would be needed if you really want to push them hard though.
I just got around to designing a suspension system for the exciters, and I tested out the updated plates on a small birthday party this weekend. The subs used was a pair of RCF 9004, and I tested with a single plate per 18" sub using an amp channel with 900w.
I used a 12 dB LR filter at 100hz for the plates, and even when pushing the amp hard they didn't start to heat up nor distort.
So I still haven't found the limit when it comes to power handling, and need bigger amp or test a single 40w exciter with the 900w amp I guess
However after an hour or so playing them at full blast I noticed one plate started distorting. One of the exciters had broken off from the plate, taking a little bit of the GPS with it. So it seems like it is too soft to attach the exciter directly to and can tear up at high enough levels.
Now I used a superglue with a spray on hardener, that has been really nice to use, but it could be that the hardener softens the EPS and it would be better to use a usual two component. I'm hoping that it will be enough to enforce the exciter area a bit. Possibly with a thicker layer of shellac or some epoxy, but worry it will affect the sensitivity. Perhaps a thin sheet over the exciter area of a less dampening material, like balsa, would be better.
Or it might indeed be the case that a CF composite is what is necessary to keep up with the stress.
Otherwise I'm quite happy with the design now. They are still stackable and the suspension offers some protection for the exciters.
It would be nice to add grills for a bit of protection...might print out something for that as well.
Will do some pics and graphs later.
So I just touched on this in previous post, but at least if you gonna hit them with far over the rated power, adhesion seems to become very important as the forces can become very strong. A good epoxy or superglue is probably best, and making sure that you enforce the exciter area a bit if you are using EPS/GPS to spread out the force. The included adhesive or very thin double sided tape will probably hold up well, but think it can affect treble response a bit being a lot softer than a synthetic resin glue.
I designed 3d printed parts to hold the exciters in place and with channels to pull cables through neatly, and added an extension at the bottom for speakon connectors. Will post actual pictures later as promised, but here is a rendering of the design for now.
I will be happy to share design files, and might even considering offering printed parts or assembled speakers in the future if I get really happy with the result and there seems to be interest.
Nice to hear that someone still animates this forum had stopped completely. IN recent months I managed to complete a first prototype with fiber and nomex, I had problems understanding how important the support of the exciters on the magnet was. Other tests were indeed known those relating to the stops on the perimeter of the frame with the plate, if I block it around the entire perimeter it is fine for higher volumes but it loses a bit on the lower frequencies, in reality there are and also many (among other things they will then be cut) if, on the other hand, I leave some areas to vibrate freely, it's better for very low volumes but then I have problems at higher volumes. In reality, I'll do the real tests soon, unfortunately I wasted a lot of time creating the frame
This is exactly my experience too.
If I'm building for hi-fi then I can get away with a much softer edge treatment, but I need to support the edges properly all the way around if I'm playing high power.
This is incredible! How much power are you actually drawing from the amp? Do you have a way of measuring?
At the moment I'm running 4 x 20W drivers per side, and I'm heating them up a little with 150W per side. But I'm driving that 150W quite hard. Not too much into clipping, but pretty close.
so for 4 40w exciters which amp do you think you would put? what a power? to avoid breaking but also to make it return. I almost certainly think of a slightly oversized amp but with a mandatory dsp to make better use of the power where it is needed, of course I am talking essentially for professional live use, for home I think it could also be fine for low frequencies so leave it in broadband.
4 x 40W exciters = 160W. Theoretically, that means you can safely use a 320W amplifier, and if you're driving 2 channels, then it's 2 x 320=640W total RMS into 4-ohms (if you've wired your exciters to present 4-ohms to the amplifier.)
Still not sure where the limitation is really. If you don't HPF they will heat up quickly even without excessive amounts of power.
But in actual use with a HPF around 100Hz it seems that they can handle a lot more than rated. I doubt that my cheap chinese amps actually deliver what they say, and haven't verified the actual output. But considering that 4 amps with a total rated output of 4000w (running in 8 ohm giving 8x 500w channels) could keep up with eight double 18" subs, I have no complaints about the power they seem to output, it is just that it is clear that the plates can handle more. And of course I don't want to push the amps that hard.
I was thinking to get a Sanway FP10000Q to run the tops of, but now I'm wondering if I should get two to drive the 16 plates with. Or maybe 8 plates and one amp will be enough unless I get some insane subs.
When it comes to DSP, it can be very nice when you have a system where the amp has presets for different speakers, and especially when they can do things like sensing driver temp to avoid thermal compression and damage. For a DIY system where you anyway have to tweak everything yourself, I'm going with a LMS unit and amps without DSP. At least with the Sanways I have now, while the DSP system works and sounds ok, I see no advantage compared to having a rack unit, but makes the system less flexible and more cumbersome to adjust.
Good morning everyone
I have to say that my system with 4 exciters with carbon-nomex panel works well, with the right power amp a really good powersoft, having said that I used a precious and very heavy and stiff wood
so now is the time to understand if I can lighten it both in terms of thickness and perhaps in terms of density of the material itself, the question for those who have experience on systems of this type to manage high powers is if, in your opinion, how can you act if replacing the wood with another material, basically I understand that the frame is crucial but I need to make it as light as possible
I have to say that my system with 4 exciters with carbon-nomex panel works well, with the right power amp a really good powersoft, having said that I used a precious and very heavy and stiff wood
so now is the time to understand if I can lighten it both in terms of thickness and perhaps in terms of density of the material itself, the question for those who have experience on systems of this type to manage high powers is if, in your opinion, how can you act if replacing the wood with another material, basically I understand that the frame is crucial but I need to make it as light as possible
Not sure I understand the question. Are you asking about how to create a frame for suspending your carbon-nomex plates in?
My solution does use wood and is still quite light. I could replace the wood with something like glass fiber and make them a bit lighter, but not worth the cost and extra work IMO. They feel both light and sturdy as they are.
But would consider alternatives if doing series production or for a certain look.
I initially thought that the frame had to be a lot more solid, but was surprised how little rigidity seems to matter and how little the frame vibrates. Thin strips of regular wood is more than enough, it just needs to clamp the plate slightly for dampening.
Can you tell me more about the plates? Have you done any measurements? How is the sensitivity?
My solution does use wood and is still quite light. I could replace the wood with something like glass fiber and make them a bit lighter, but not worth the cost and extra work IMO. They feel both light and sturdy as they are.
But would consider alternatives if doing series production or for a certain look.
I initially thought that the frame had to be a lot more solid, but was surprised how little rigidity seems to matter and how little the frame vibrates. Thin strips of regular wood is more than enough, it just needs to clamp the plate slightly for dampening.
Can you tell me more about the plates? Have you done any measurements? How is the sensitivity?