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Triumph Don
12-02-2008, 11:09 AM
Any opinons on what components would work best in upgrading the Jubal crossover? Woofers are 126A. Thanks!

timc
12-02-2008, 02:25 PM
I have a pair of theese with the 126A woofer.

I changed the capacitors to Solen polypropylene and it made a good bit of difference. Guess the originals where pretty dry. I might try a CC network for them in the future.

The difference i noticed was less hiss from the midrange and tweeter. it sounded smoother, so the details was easier to hear.


-Tim

markd51
12-03-2008, 08:26 PM
Any opinons on what components would work best in upgrading the Jubal crossover? Woofers are 126A. Thanks!

Some years back, I guess I got a little carried away, overdriving my four Jubal Speakers one evening, and totally fried the X-Over Networks in two of them.

I of course had a couple of different choices, re-build what was in there, or start all over, with totally new, better quality X-Overs.

I opted for the latter, and after some research, I found a couple of companies wishing to charge me an arm, and a leg, I found Madisound would make what I wanted, and at a very reasonable price.

After getting the specs from JBL, I faxed them off to Madisound, and had them make me four brand new complete X-Over networks, using Goertz Alpha Core Air Core Inductors, and all Solen Caps. What came, where four unbelievably beautiful massive X-Overs. I also bypassed the wimpy, and half shot L-Pads, installing thier 100W models at rear of cabinet, and four brand new Edison Price Billet Copper 5-Way Binding Posts.

I have heard it said once, that if a speaker originally uses Iron Core Inductors, that one should perhaps stay with them, but I have noticed no downside to using the Goertz Air Core Inductors.

I went further to better interally brace the enclosures, fillet all joints, and of course used high grade internal wiring throughout. I also foam gasketed all 126A Drivers.

Of course, I took my speakers from being all totally original JBL, and perhaps have "ruined" thier vintage value. I had no intentions of ever selling them, and the upgrades did proove to be sonically advantageous.

It's been about 7 years since the upgrade, they're still playing amazingly well, and since I stuck with factory values for the Caps-Inductors, the wonderful Jubal sound was not lost. The entire spectrum became cleaner, purer, bass was cleaner, tighter, better defined, mids smoother.
Mark

3dbdown
12-03-2008, 11:36 PM
The Solen's willl be a remarkable substitute for the original caps. Iron core inductors are OK in woofer circuits, but the air-cores will be much more stable at higher frequencies. I don't know how much, if any, difference it would make in the original network, but they don't really go bad anyway. I didn't see any need to change mine, so they are original. Charge Coupling is best, but much more money. Twice as many caps at double the capacitance, and all....

I love my Jubals with Solens. There are other cap choices out there, but I personally like Solen sound in JBL's.

Rick