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BillR
04-15-2010, 04:09 PM
Do speaker spiders collapse and what causes them to do this. Is it repairable and how can you be sure the spider is damaged?

herki the cat
04-16-2010, 12:04 AM
Do speaker spiders collapse and what causes them to do this. Is it repairable and how can you be sure the spider is damaged?

I assume you have damaged 2245 with some problem around the voice coil or the spider. Could you provide a complete description of what you experience and see in your 2245...voice coil stuck, or rubbing, whatever..please. I have several 2245's & maybe able to help you.

herki the cat

BillR
04-16-2010, 07:43 AM
Thanks Herki the cat for replying. This 2245H needs to be refoamed, and am wondering whether this is the reason for the spider sagging. The voice coil seems to be ok since I can jump it with a flashlight battery and get noise. You can make the voice coil rub by pressing on one side or the other and pressing down. Other than that, is the best I can tell you at this time. The rest of the speaker is in great condition. The cone seems to be the original. What do you think?

pantaNS
04-17-2010, 02:09 AM
Maybe it was stored for a long while upside down? That could cause spider sagging, but it is repairable . . .

herki the cat
04-17-2010, 03:45 AM
Thanks Herki the cat for replying. This 2245H needs to be refoamed, and am wondering whether this is the reason for the spider sagging. The voice coil seems to be ok since I can jump it with a flashlight battery and get noise. You can make the voice coil rub by pressing on one side or the other and pressing down. Other than that, is the best I can tell you at this time. The rest of the speaker is in great condition. The cone seems to be the original. What do you think?

BillR; IMHO since you find the voice coil is not rubbing it is quite possible refoaming maybe all you need. The professonal speaker repair people like Member Edgewound can examine your speakers and restore them like new JBL's.

You can have a preliminary look if you wish to examine the cone stability, you can proceed in three steps; but ultimately, please have a professional do the restoration.

# 1)...First...Hold the 2245 with the basket face in a vertical position, same as when mounted in the cabinet. Now if the foam surround is mostly deteriorated and will not support the cone normally, you will see the mass of the 18 inch cone pull the cone downward making the the spider bend nearly symmetrically like a hinge, only if the spider is in good condition.

However, if the spider is damaged and has lost its normal flat shape and spring qualities then i would expect the cone mass to pull the voice coil forward and the entire spider to move some what intact forward.

#2).....Lay the 2245 flat on its back side and look for any deviation from a nearly perfectly flat spider shape , which will be the case if the spider has lost its its spring qualities. A damage spider will either poke up or sage down if it has lost its spring qualities or normal flat shape.

#3).... Place the 2245 face down supported so the cone can move down & out __in case the the spider is weak and damaged __ and look for any deviation from a nearly perfectly flat spider shape , which will be the case if the spider has lost its its spring qualities. A damage spider will either poke up or sage down if it has lost its spring qualities or normal flat shape.

Be aware that a spider can be damaged in two ways:.

#1) if the speaker is over driven and the voice coil slams into the motor structure, the spider can also slam into the motor structure losing its shape.

#2) Long term storage with the cone face-up or conversely, face down. This will slowly pull the spider out of shape for good.

herki

JBL 4645
04-23-2010, 11:59 AM
Is it possible to see a picture of the supposedly spider issue.

I just looked at the spiders on the other JBL speakers, just to make sure they’re not sagging or showing signs of deformity. Creepy buggers they are.:D