I blew up my beloved JBL mpro 418s driver

No, two fingers should be enough. But wait until you get it back working properly. However they must be your own fingers! No cheating.
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Don't expect any more business from me or Billy Joe Shaver (R.I.P.) ;)

Art
 
The speaker 2241g rated at 40V, amp rated at 66V so It's about 1.5Xcontinous. It was loud (to me) at the time as I was by the sub. I have the DBX DR260 setup cut off at 40Hz. The amp was clipping for sure
Power to voltage ratio is exponential, so 66V is ~2.7X the maximum power allowed.
If to boot it was regularly clipping, even worse.

No surprise you fried that voice coil.

Nobody suggests you recone it, just get an aftermarket recone kit (original will be too expensive) and have the job done by a Pro.

And next time set up your limiters to a sensible value, definitely not clipping and not above 600W RMS.
 
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Don't expect any more business from me or Billy Joe Shaver (R.I.P.) ;)

Art

I have fired folks who I strongly suspected if still working for me would have injured themselves. One fellow actually put his hand in the gap between two loaded beams to try and close the gap. Had the beams moved he might have kept his thumb.

The normal thumb remover is a table saw. I got the European version with a sliding table and covered blade after a few hints from my old one.

The multiple finger damage often comes from a wood shaper, mine has a power feed to try to avoid that. Although we don’t really use it. Instead I have a small router table.

One interesting thing I have noted is that many of the more than 40 scars on my hands are healing and have disappeared. I think this may be due to having started high blood pressure medication!

I used to have trouble telling left from right. The I realized I had a scar on the back of my left hand. So I would look at my hands to see which way was left! After a while I realized I was only looking at my left hand. That was when I finally had learned which way was left. Fortunately the educators then did not seem to know about dyslexia back then. So I just got bruised about bad handwriting and not sidelined as “Special Education.” Typing was a help but personal computers didn’t become a reality until after college. So some scars were actually useful!
 
Again, comparing specs using a Margolis/Small max flat BR for reference, the 2241 calcs a ~66.98 L/45.76 Hz alignment Vs the APX-1841-8R's ~617.27 L/22.31 Hz, so a very poor fit in the MP418's tiny box, though presume it can be DSP'd to work well enough.

In short, Qts' dominates until Vas is quite high, so either have to find a tiny Vas and/or low Qts' or some balance between the two along with an Fs within ~0.707*Fb to give you some port fine-tuning flexibility.

net volume [Vb] [L] = 20*Vas*Qts'^3.3

box tuning [Fb] [Hz] = 0.42*Fs*Qts'^-0.96

[Qts']: [Qts] + any added series resistance [Rs]: http://www.mh-audio.nl/Calculators/newqts.html

[Rs] = 0.5 ohm minimum for wiring, so may be higher if a super small gauge is used as a series resistor and/or there's other series resistance.
 
Thanks, you usually give out formula equation and such etc.
So, fb=70Hz and fs=0.707X70=49.5Hz
The measurement shown it measures down to ~50Hz and fairly flat to 100Hz which I am now cross.
In my situation getting a re-cone or buy another one wouldn't be an economic sense.
If anyone want the 2241 magnet it's free you only pay the shipping.:cheers:
 
JMFahey, I am not too sure to understand I thought I could go to 2X continuous for peak or maximum, on JBL rated at 40V then 80V is for peak to get the maximum usage out of the driver please explain.
Literally basic Math/Electronics/Physics: power to voltage ratio is exponential, so 2X voltage (your 40V>80V example) means 4X the power, NOT twice the power.
Or in your case: 66V means 2.7X the power applied with rated 40V.
A GROSS overload if you ask me and not surprised those voice coils were destroyed.