4311 Monitor X-over Capacitors

[wdascenz]

A question to my brother JBL owners.

The 4311 has a simple crossover using 3-ufd and 8-ufd film capacitors. As I understand it these were sourced from IMB in California and measure better than anything I have in my bag of tricks that were candidates as replacements. My inventory of passive parts includes polyester (Mylar), polycarbonate, polyenthylene, and polypropylene capacitors suitable for use in high-current speaker crossovers.

Has anyone out there in JBL land found out what these are? They are encapsulated in a card-board tube with radial leads. Because of the way they measure (and sound) I suspect they are polystyrene capacitors. I am not sure IMB made anything else other than Mylar and polystyrene capacitors at that point in time. I am guessing they made polystyrene since they served as a supplier to military contracts.

Any information would be most appreciated. Thanks.

Walt

[duaneage]

They are oil filled caps and can be replaced with better. Decent Mylars or Polypropylene would be ok. Bypass them with .1 uf caps for even better results.

[Zilch]

Cardboard cans with the paraffin-appearing seals?

They're sand-filled mylar, I believe.

[Or maybe the oil leaked out.... ]