Scorpion 12" - Xmax?

[Dix]

OK, so I was bored yesterday waiting for the Super Bowl to get started & playing around with WinISD for giggles when I think I found an error in the Scorpion TS spec sheets.

Someone correct me if I'm wrong here, but I believe the decimal point for the 12"s Xmax is in the wrong place.

I was always under the impression that all the Scorpions used the same basic voice coil. So the 12" Xmax of .25mm seems awfully low when compared to the 15" with an Xmax of 3.1mm.

So I take a look at the old (2005?) spec sheet that includes the old 10" & that lists the Xmax of the 10" at .06mm. Which might lead you to believe that the Xmax of the 15" is wrong, until you notice that the Vd for the 10" is listed as 19 mL.

Not only does that give the 10" a greater Vd than the 12" (12.5 mL), but coupled with the Sd of the 10" at .031 sq.M., the math doesn't work.

.031 sq.M. = 310 sq.cm.
.06 mm = .006 cm
310 x .006 = 1.86 mL not 19.

.06mm is barely 2 thousandths of an inch. & 1.86mL isn't much. For an idea of exactly how little... it's less than half a teaspoon.

That's when the lights came on, & I suspect that the Xmax for the 12" (& the old 10") may simply have a misplaced decimal point. & comparing it to the spec of other 12" drivers of similar performance has that suspicion making a certain amount of sense.

I believe the Xmax of the 12" should be 2.5mm rather than .25 as listed. & coupled with an Sd of .05 sq.M. would yield a Vd of 125mL. Which makes a lot more sense.

Likewise the old 10" should have an Xmax of .6mm with the listed Vd of 19mL being correct.

The 15"s Sd of .084 sq.M. & Xmax of 3.1mm works out to a Vd of 260mL, not the 227mL listed. So exactly how that math works I have no idea.

[Sir-cranks-alot50]

I think that's right the 15 is more for bass them are for guitar.I would imagine any guitar speaker don't move too much.

[Dix]

Except that the Scorpion line (as memory serves - which granted, at this point is always questionable) were never exclusively instrument amplifier speakers (hence the cast frames), and were used in a lot of the budget sound reinforcement cabs in the past.

Compare them to something that they were actually comperable to in real-world performance, such as EV's old "Force" series or JBL's old D/E series, and the misplaced decimal point starts to make a lot of sense if you're comparing the results you get in simulation software.

For example, if you use .25mm as the Xmax you can't even put it in a 1 cu.ft sealed box without exceeding the Xmax at about 150Hz... at 1 watt.... put the continuous 200 watts to it & you're over the Xmax up over 500Hz... & that's in a sealed box.

Now, if that's all correct, Scorpions would have about instantly destroyed themselves in near any open back combo amp.

Obviously, since that didn't happen, I'd assume the spec sheet is wrong.... either the Xmax simply has the decimal point in the wrong place, or the specs with regard to suspension stiffness, etc, are way off.