My JBL XPL200A's

[Riley Casey]

One possibility would be to remove the existing crossovers and trace out their circuitry and then post the schematic here and ask if someone familiar with charge coupled crossovers to design the required changes. I suspect that by the time you got up to speed on reverse engineering the stock crossovers you might be skilled enough to rework them yourself. It's not terribly complicated with an existing circuit.

... I'm spinning my wheels right now...

[Ian Mackenzie]

I wanted to make charge coupled crossovers for my XPL140s. I built them according to the XPL140A schematic. I was gonna pull the capacitors and wire the charge couple capacitors in their place. When I got into the JBL crossovers, everything was differnt from the 140A schematic. Different resistor and capacitor values and components in different places to name a few. Maybe they are XPL140s and not 140As? I've looked far and wide for a different schematic and contacted JBL. It's impossable to find any other schematic for this speaker. i've looked around on this site. I'm getting nowhere. I've got a bunch of parts that I can't do anything with if I can't find a good schematic. Any ideas?

Can you post a picture of both sides of the pcb ?

I might be able to confirm which version you have.

[Rusnzha]

Here are the pics of my crossovers.

I know how to make the charge coupled stuff, but I have a lot to learn about the rest of the circuit. I will build from scratch, I don't want to mess with the original crossovers and more.

[Ian Mackenzie]

For your clarity,

A note from the designer:

“Should be a label on the back. The XPL should have an HF level switch which goes 0 and + 2. The XPL-A should go 0 and -2. The XPL uses a 095Ti midrange and the XPL-A uses a 093Ti. The midrange would have to be removed to verify.”

GT.

[Rusnzha]

The switch on the back said +2 and I have the 095 mid so it's definitely an XPL140. This still doesn't tell me much about the crossovers. I want to build them from scratch and keep the original ones intact. I looked at some crossover constructors, but they don't look good for making charge coupled. I have a few things to learn before I can move on this.

[Ian Mackenzie]

There is no schematic available. However if you read the cap values in the mid and HF you can then work out your charge coupled parts values from there.

[Rusnzha]

I already have all the charge coupled stuff for the crossover in the schematic. I will attempt to rebuild the newer crossover from scratch with better parts and the inputs charge coupled. I don't want to mess with the originals, I would have to take them completely apart to know what's in there. They are working fine right now, I'm not taking any chances on screwing them up so this is the plan. Thanks for your help with this, it did me good.