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View Full Version : Need help rebuilding crossover



scorpio
11-15-2005, 10:18 AM
I am running a 2ways set up xith LE15A and LE85, I am using a old crossover from a L200b for this. I kow that the L-PADs on these Xovers are starting to fail and also guess that most of the condos would benefit from replacing.

So, I decided to rebuild a copy of these using fresh, good quality components. I have one problem, I cannot find 16 ohms Lpads as specified by JBL, only 8ohms (see crossover schematics attached).

Could someone confirm my calculations (this is really not my stuff) that replacing the Lpads for 8 ohms, I should just change the resistance labelled 13203 from 5 to 7.5 ohms and everything should be OK?

Also, what is your opinion on the usefulness of keeping the LCR cell on the HF channel considering I only use a flea-power amplifier to run these, what would happen if I ommit these parts?

Zilch
11-15-2005, 10:37 AM
16-Ohm L-Pads are available at Parts Express, OR, use fixed resistors to substitute for your standard setting.

It looks like 7.25 is the number you want for your approach. Give it a try, maybe. You're ignoring the driver impedance, is the problem with that method, tho. LE85 is effectively 10 Ohms through the HF range.

The LCR cell is your HF boost. It'll sound worse if you omit it, unless you've added a supplemental UHF driver....