Seas Excel Graphene?

I saw this month ago, but seems nobody's talking about it?

I wonder what that will be?

In my knowledge, if it's true, this is the first real graphene speaker?

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Yeah, as I said elsewhere, we'll have to see some measurements to see just how much difference the FEA optimised motor makes to the overall performance.

The breakup shift is nice and it'll be interesting to see if it continues across the other drivers in the range. In other words is this because of the graphene or because they've reworked the cone profile slightly.

I suppose I was hoping for something completely different from SEAS. We've already got SB acoustics producing metal cone drivers without the usual HD peaks associated with them. Will this graphene coating make a considerable difference here?

I guess I was hoping for a thin sandwich type cone with grapene skins, giving very high stiffness, so no breakup within the passband, like the metal cones, but with high internal damping so that nothing propagates into the HD.

I guess the impedance blip at 5-6.5kHz isn't as severe with the graphene driver, even if the actual SPL peak is worse.
 
I guess much lowered inductance made the peak higher.

Also, higher QMS will remove some mech damping, but I'm not sure how much the QMS effects HF. A MarkAudio article talked about this effect(Alu voice former) which seem to be significant.

But yeah, since we have the excellent SBA NAC drivers, bigger SD, even higher freq breakup, much cheaper/ lower tech. I think it's fair to expect a driver with no much breakup at this tech level. Something like SCM634 maybe.
 
It's a good way to improve the weakness of the magnesium excel range ie the break up. Not sure the naked copper suits, wd like to have seen a new phase plug colour (and shape?) to go with the cone. A matching grey wd look sick

Still, the mid version shd be v nice
 
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Finally very nice new metal driver from reputable manufacturer. Primary break-up moved 35% higher in the frequency range, considerably higher continuous power handling, much lower mechanical losses and greatly reduced coil self-inductance both nicely reflected in the impedance values clearly visible on graph. All of those solid performance indicators will definitely cause serious upgrade to top-performing yet very expensive Excel line. HiFiCompass, do you hear me? :)


And obviously lots of other's complaints becouse of something new. :(
 
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I always wonder what caused the small bump in the area of 400-600hz in many rigid cone drivers.


Cone edge becomes to decouple from surround which causes sudden moving mass decrease with rising frequency. Cone starts moving without part of surround and it already tends to bend slightly, efficiency of radiation rises, so sensitivity goes up a bit as a result. Do not confuse it with break-up, driver is clean for another few octaves up (or even full decade if surround is particularly soft).

Soft cones can tame its surrounds when they are going wild but obviously it is reflected in energy storage increase, despite SPL jump removed from nice graphs. Rigid membranes are free from energy storage until primary break-up frequency were piston motion finally disintegrates.
 
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There is no such thing in SB15NBAC nor SB17NBAC. Engineers from Seas could use a lesson or two from guys from SB. Taming the breakup also.


Excel still uses straight cones whereas SBxxNAC have smart 2-staged, curvilinear cone shape with additional slits and these cool features combat with surround wildness and break-up mode Q value very efficiently with little penalty in reduced stiffness and little increase energy storage (kept on unmeasurable level, impossible to avoid physically). On the other hand, Satori line of woofers was plagued with this issue. NAC drivers serie is a wolf in sheep's skin.


But wait, surround detachment is clearly visible on SBxxNAC measurements, racingpht already has posted it. :)
 
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I believe it is already fixed in SB15NAC as well, they thickened inner part of surround and made surround - cone edge overlapping area broader. I am keeping those drivers in hands althought I have no time to mount them and measure. :(

What do you mean "fixed"? Are there two revisions of the same driver?

I have SB15NAC, but same here: No proper measurement.

BTW, the bump was not seem in this build:
SB 23 TL (Transmissionline) - Mai 2016 - Lautsprecherbau-Magazin 2016 | Lautsprecherbau - Lautsprecher selber bauen