I know there are a lot of smart people here, so I thought this would be a good place to ask. What are the advantages of dual spiders? All I can see is bad things from this design. But TC sounds seems to prefer it. To retain your excursion, you have to use smaller spacers and smaller roll spiders. This means that your Kms curve, which was already parabolic, just went VERY parabolic. So to add this kind of handicap, there must be a benifit somewhere with using dual spiders.
While I don't believe overall it is advantageous to have dual spides, one advantage is that your pivot point has just become larger. With a rather limited understanding of physics one can see how this applies to torque on where the cone attaches. Instead of piviting at one point with a single spider, the dual spiders have a pivot point that bridges the gap between the two spiders and the spiders themselves. Hence, less torque on the driver. That's the theory. How big of an advantage this is...you decide
Wheres Geo at For instance, on the A series the A has 2 spiders, 8mm apart(thats pretty damn wide) as mentioned above, this changes the pivot point, which should increase suspension compliance linearity as far as to how much.... i dont know, but ive seen the dumax of the 12a, and its DAMN flat kms but.... look at the W7, that has the best compliance curves i have ever seen, and thats a single spider
??? how does it increase linearity? mechanically, it can help with keeping the cone/VC assemply from rocking side to side....(?)
But K, that is not compliance linearity Compliance linearity is simply accomplished by the spiders and surrounds and a single or dual spider will have no affect on compliance linearity We had a discussion about that here before actually Steven, in which Dan offered some valuable insight (I too was puzzled by its effectiveness and was interested in why we didn't see more of them) 3 big thoughts I will leave you to ponder, as I am about to sit down and watch a porn... uhh, movie with my wife . What easier way to manipulate FS in heavy piston drivers? What easier way to shrink the box size? What easier and safer way to reduce mechanical failure due to unloading or otherwise overdriving the sub?
Awesome. I shall do a search. So they needed a stiffer suspension beyond what a single spider could offer? Actually there is an easy way to do this, without adding such large negatives. You could add shorted turns to the sub, which acts as a brake.
This is where it get's complex. They originally used higher roll linear spiders, but were limited on excursion. So they switched to a smaller spacer, and used lower roll spiders. This is how they got the excursion's listed, but their Kms curve just went VERY parabolic. Did you note the Xmax on that DUMAX report? I'm wondering if the one you saw was before or after the change in the spacer. But what you describe above doesn't sound like what Dan told me the Kms curve is like with either spacer.
Not too sure what MMS is on the drivers in question, so I dare not answer with a poorly researched answer. My assumption is, yes. But, I suspect they are used for this, and to also aid in the following: By reigning in a heavy cone with a single spider, it would have to be quite stiff. Maybe the designer (or buildhouse) realised that this might affect the throw of the drivers. In this age of "superwoofers" we are looking for the greatest throw. However, we are also looking to maintain some semblance of linearity. By spacing the spiders apart, we are adding to linear excursion, reducing overall audible distortion, by reducing cone rocking at high excursion. I see the wheels turning here Steven, but again we need to consider the effect that using 1 method of controll has on the other variables (and target goals) of the driver. Adding a shorted set of coils is a great way to brake the driver and reduce the possibility of overdriving the woofer. It is also a great way to add weight (re: Mms and Fs issues) which in turn brings us all the way back around to needing to stiffen the spider to regain our target Fs... Damn the compliance issues !!! So, what is the easiest way to achieve all of our goals? Dual spiders
Well I did the search, and found my answer. Here's what Dan said: So linearity is not effected, but in a way can be worsened. In fact, here's what I found at TC Sounds site, who seem to be the proponents of dual spiders, among other things: As you can see, it is curved and would result in a parabolic Kms curve. And I should mention that a lot of their customers seem to use dual spiders, that don't have heavy cones. So it sounds like they push it for more than just for heavy mms designs. Do they use longer coils than normal SGLC motors? Or do they try and have a smaller gap than usual to require more rocking control? Also, does anyone know which TC motor the ED A uses? My guess is the 3HP?
I'm pretty sure shorted turns add very negligable weight Mr. Devil's Advocate. BTW, you still need to empty your e-mail inbox. I keep getting messages saying it's full when I send stuff to you.
well, here's the link for other people who are too lazy to link to it i mean, to search for it... dual spider discussion here's a quote from warbleed talking about an lvs sub in that thread pg.3 hmmm... what does that mean? each spider must be really linear so that having two of them wont affect the linearity?
Emptied. are you sending it to the e-mail attatched to this forum, or my sales Steven? My sales site should not have been full. sales@sound-foundations.us there is the link for you B)
Emptied. are you sending it to the e-mail attatched to this forum, or my sales Steven? My sales site should not have been full. sales@sound-foundations.us there is the link for you B) [/b][/quote] How do you check it? Web mail or a Desktop cleint?? Defualt on Cpanel is 10mb qouta, if your getting a full message 1 that is a shit load of mail 10MB, but if your using web mail all the time and keeping it in the inbox it can build up over time you can increase that quota easy enough though
Ok, it is sent again. I can't wait to hear your thoughts. Chris must have gotten busy and didn't respond. But I understand. Anyway, back to the dual spider issue. I just noticed something on HTF about Janowitz switching from a single progressive spider to dual flat spiders in his AV15's. I asked him why. Here's the link. I'm kind of curious about his answer.
awnser my question go in to your Cpanel, and see how much disk space your using, then go in to your email account lists and adjust the quota for your sales account higher if your using a Email cleint make sure you deleting the topics from the inbox after downloading if your using web mail just tyr to only keep important stuff, and increase your quota size if your getting THAT much mail, maybe you should consider a ticketing system to help you organize it. even with my old sale account getting over 500 SPAM messages a day I still did not fill up my box
