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WillyD wrote:
 I am sorry, but are you saying xmax is an informal standard but Vd is set in stone as peak to peak displacement?
Thats a bit odd, don't you think? |
Yes, it is. I suppose Vd might not be set in stone, but I do believe it's typically calc'd using peak-to-peak excursion. In any case, I suppose we could check with LinearTeam to see which way they intended the Xmax to be entered. A definitive answer on this would be nice.
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Xmax is almost always given as the one-way linear excursion. I can't think of many examples where it isn't. Its not our fault that in WinISD, the formula used to calculate Vd is simply xmax x Sd, when usually it is 2 * xmax * Sd. I don't know why you think you need to put in the peak-to-peak xmax simply because of this.
"Having the right Vd value for your model" is completely irrelevant. That value it gives you for Vd is not used in the actual simulation. You only need to pay attention to what the simulation gives you (i.e SPL)
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Absolutely. I was only using Vd as a means to understand how to enter the Xmax.
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And you're correct about the resonance, 156Hz shouldn't be much of an issue. Do you actually have any intentions of building an 5400 LLT? That would be interesting..to say the least.
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Yes it would. I don't know that I'll do it using the LMS driver just yet, but I'll probably put an LLT together using either a 12" or 15" TC-2000 to evaluate it vs my sealed subs. I'm leaning toward using Sonotube in this effort, even though I've never built a sonosub before. The larger enclosures required for LLTs would make MDF enclosures extremely heavy and difficult to work with. So, for those of you who have built sonotube enclosures and don't mind offering up some of your wisdom on what works and what doesn't, I'd be interested in hearing it. Stuff like how to make an endcap. A Jasper Jig will cut a disk about 18" in diameter, but not 24" or 30". How is it normally done? I suppose I could rig something to use as a pivot for a router...