Defect capacitor on JBL 4344 ??

[Madien3388]

Hi,
I recently replaced the binding posts of my 4344 and discovered that one capacitor has a strange aspect when dismounting the filters.

I have been told that all capacitors of this JBL monitor were in polypropylen, not chimical ones. Only chimical capacitors flow when they are dead, so it shall not be the capacitor but the glue used to stick the capacitors on the filter?

If anyone would be able to help me on this, it would be great. To know if it is only the glue which has flown under the capacitor or if it is the capacitor which is dead. I'm started to worry ...



Many thanks in advance !

[Chas]

Bonjour Madien 3388. Actually, I believe the capacitors were Mylar in the 4344/4345 networks. When I looked your pictures at first, I thought it was simply the hot glue used to secure the cap running down the board. I have never seen anything like this oozing from this type of capacitor construction. the ooze is a different colour than the glue.

You could remove it and measure it. Or better yet, simply replace it.

[Madien3388]

Bonjour Madien 3388. Actually, I believe the capacitors were Mylar in the 4344/4345 networks. When I looked your pictures at first, I thought it was simply the hot glue used to secure the cap running down the board. I have never seen anything like this oozing from this type of capacitor construction. the ooze is a different colour than the glue.

You could remove it and measure it. Or better yet, simply replace it.

Thank you Chas! I am quite lost as polypropylen capacitor doesn't do that when they are dead.
The liquid is very solid, like the glue under the capacitors. Liquid from chimical capacitors is not so solid, more sticky.

I am quite afraid to remove it as it seems that the speaker works great... but it bothers me much !

How could I know the type of the capacitors ? Polypropylen or not ?

Where can I find the 4344 schematics to find out the function of this capacitor (is it used for the 2235, 2122, 2421,2405 ?)

Many thanks
Damien

[jcrobso]

http://www.mcmelectronics.com/product/50-4566

[Ian Mackenzie]

Looks like Alien goop!!

Its a shunt capacitor in the horn filter.

I would be inclined to leave it alone unless the substance is effective / contaminating other components.

Ian

[mech986]

3144 network, charge coupled version.

http://www.audioheritage.org/vbullet...25&postcount=5