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I got a little more insight, Geo

http://forum.elitecaraudio.com/showthre ... enumber=11

Dan Wiggins wrote:
The ripple comes from pushing excursion as far as possible, plus a few other special sauce things, but it is by no means always present with an XBL^2 driver. If we bumped the motor design a bit more to gain 15mm Xmax or more, then you'd see a ripple start to develop.

ANY nonlinearity of the BL curve will cause a rise in distortion products. Having a BL that drops approximately 2% from the "rest" value leads to around 0.3% THD. If the drop is symmetric in distance and amplitude from rest, then it's pretty much all 2nd order THD as well.

This is one of the actual benefits of XBL^2. A designer can, if desired, allow a certain amount of distortion into the system while gaining more stroke (or a shorter voice coil). In some cases, like musical instrument speakers (guitar cabs, for instance) this is actually a good thing, and you want to add quite a bit of THD (5%+). In other cases, you can allow THD below the limits of audibility, but still measurable, and gain other benefits.

Maybe my idea wasn't TOO farfetched

well, by chrome I was thinking along the lines of the XXX magnets.. that didn't look bad really on the gen one models.

Now if you go with the punk spikes, I think it needs a deep purple surround to go with it, and maybe one of those translucent dust caps with LEDs under it so it glows.
Could I get mine with a Sid Vicious bobble head doll?

Thx for the info Geo. I'm guessing the CSS mid was just the result of a lot more work on FEA modeling, then I didn't know exactly how much flexibility it really offered, now I know.

geolemon wrote: Anyway - with the XXX moving right up out of there into an expensive driver (it does look cool), and the Brahma becoming scarcer and scarcer, there's an opportunity I think with an already existing customer market - although we've really technically been targeting the W7 as our benchmark standard, driving a lot of the design, a lot of our modeling comparisons, if you will.

But I'm a longtime JL fan, so maybe I just gravitate that way.

Protos look great. If you have the BL curve you posted, plus a suspension as capable as that of the W7, you have a winner

Thx for the info Geo. I'm guessing the CSS mid was just the result of a lot more work on FEA modeling, then I didn't know exactly how much flexibility it really offered, now I know.

geolemon wrote: Anyway - with the XXX moving right up out of there into an expensive driver (it does look cool), and the Brahma becoming scarcer and scarcer, there's an opportunity I think with an already existing customer market - although we've really technically been targeting the W7 as our benchmark standard, driving a lot of the design, a lot of our modeling comparisons, if you will.

But I'm a longtime JL fan, so maybe I just gravitate that way.

Protos look great. If you have the BL curve you posted, plus a suspension as capable as that of the W7, you have a winner

porcelian (sp?) dustcap?

GlassWolf wrote:thanks. just made it up :)
thanks for the image. looks lovely. I like these new terminals everyone uses now with posts instead of the old spade terminals.. man I used to hate those things. ugly, wires fell off half the time from resonance, no ay shy of solder to keep em fixed, and did I mention ugly?
I beg of you, have a sexy cone though. I like the simple elegant cone designs like the eclipse Ti has, and even the XXX, if any design is used at all. Nothing gay like kicker et al, with raised fancy designs and explosions etc. bling drives me up a wall, although a little tasteful chrome is always the sex :)

Sex...

I was thinking about a black rubber coated cone, with about 14 three inch long chrome punk-rock spikes bedazzled to the cone, sound good?

Actually, I think we'll have a pretty upscale looking sub here...
I think I'll hold off on final details regarding the cosmetic touches, but they will be upscale, and will not be bling-bling... no chrome, sorry.
(but a metal plating - yes! Matching dustcap - yes! Hmm, what could that be? )

thanks. just made it up :)

thanks for the image. looks lovely. I like these new terminals everyone uses now with posts instead of the old spade terminals.. man I used to hate those things. ugly, wires fell off half the time from resonance, no ay shy of solder to keep em fixed, and did I mention ugly?


I beg of you, have a sexy cone though. I like the simple elegant cone designs like the eclipse Ti has, and even the XXX, if any design is used at all. Nothing gay like kicker et al, with raised fancy designs and explosions etc. bling drives me up a wall, although a little tasteful chrome is always the sex :)

GlassWolf wrote: I'd hate to pet a bunny with a bulldozer ya know.

thats an awsome referal to kicking the crap out of a sub i might have to use that some time.

Ballpark, yes.
Still have some finalizing to do - researching shipping rates, awaiting final billing, etc.

Anyway - with the XXX moving right up out of there into an expensive driver (it does look cool), and the Brahma becoming scarcer and scarcer, there's an opportunity I think with an already existing customer market - although we've really technically been targeting the W7 as our benchmark standard, driving a lot of the design, a lot of our modeling comparisons, if you will.

But I'm a longtime JL fan, so maybe I just gravitate that way.

Oh -
I promised a preview picture.
So anyway, this is just a picture of a preproduction test mule:
(looks like I took it in a photography studio, no? )
The finalized version is going to have a few upscale cosmetic touches.

oh in regards to the membrane, I was going to see waht I could find for a thicker material for the membrane to withstand the pressures, at last to sandwich something lighter to fine tune with.. then probably squish all of that between stel mesh not unlike a screen door material to hold it firm, maybe over a wire bead. That'd allow it a lot of rigidity and I could still cover it with an acousticly transparent grille cloth dyed to match the interior for a stelthy appearance.
Just some ideas I've tossed around. I knew the displacement would be a factor to be concerned with on a sub like that just like it was with the XXX12.

The 2250SX on one of these won't be an issue will it? Albiet they won't see the full power (I feel like Darth Vader) of the deathst, er, amplifiers, I'd like to make sure I don't kill them by accident. I'd hate to pet a bunny with a bulldozer ya know.

I know what you meant about the AP membranes and older subs, too. I still have my (at the time formidable) Cerwin Vega LE12D subs, with all of their 14mm Xmax.. haha circa 1989, but they were madly efficient so even with 160 watts each two of those babies could really give my car a workout for the era. I have seen S12L7 and S15L7 solobarics in AP enclosures though so it's still done sometimes with newer drivers.. though I'll admit if ever there was a sub that could use more control and better SQ, it's a solobaric.. haha