Restoring JBL L-65 Crossover Advice?

[TurbineShake]

Hello Techies out there! Where is a qualified technician when you need one?
I'm in the process of restoring some old JBL L-65's that some nuts gutted. The crossover functions fine but, I was wondering while it's all apart would some improvements be practical. Those capacitors look really old and what would I replace them with? The same values but just the newer audio designed caps?
Please someone advise me. I like the electronics part but, I'm no expert! Newbie please!

[edgewound]

You might try some Solen Fastcaps...metallized polypropylene 250-400volts. Not too exotic-expensive, and the perfect -layer aircore inductors. Nice upgrades and simple straightforward replacements.


Some other forum-members are hot for charged-couple networks...maybe they'll give some input too. L65's are great speakers...have fun with them...and you're a near saint to resurrect them:) .

[Robh3606]

Which L-65'S do you have Jubals, A's or B's?? To see the Jubal uses the 126A the A a 122A and the B a 129H. In the A and B versions L3, shunted across the midrange driver, should not be changed unless you match the DCR. In general if you change out any of the inductors measure the DCR first. The DCR for L3 is 7.5 ohms. Droping in a low DCR coil is going to change the F/R of the midrange driver. In addition the inductor in series with the 077 is a taped custom inductor. You should leave this one be.

Rob:)

[John W]

I bypassed the larger capacitors with some .01uf caps in my L65s with good results. At this size they are not too pricey, even for the boutique brands.

[JanB]

Anyone who can tell me the value of the two large caps in the dividing network for the L-65 Jubal?

[hjames]

Anyone who can tell me the value of the two large caps in the dividing network for the L-65 Jubal?

Schematic for L-65 is here:

http://manuals.harman.com/JBL/HOM/Technical%20Sheet/L65%20Jubal%20ts.pdf

If needed, L-65A is here:
http://manuals.harman.com/JBL/HOM/Technical%20Sheet/L65A%20Jubal%20ts.pdf

[JanB]

Thank you very much!:)

[rgwalker]

You might try some Solen Fastcaps...metallized polypropylene 250-400volts. Not too exotic-expensive, and the perfect -layer aircore inductors. Nice upgrades and simple straightforward replacements.


Some other forum-members are hot for charged-couple networks...maybe they'll give some input too. L65's are great speakers...have fun with them...and you're a near saint to resurrect them:) .

I just upgraded some Model 19 crossovers with Solens fast caps and North Creek air coils. The coils were pricey and very large and I had to mount them outside the crossover box but it is an amazing difference and well worth the price. I swapped equal values and it was an absolute no brainer.

Bob Walker