Xover troubleshoot

Concerning my Chartwell LS3/5A's:

I have made a couple clones of these lovely 44 year old speakers, because i love them so much. but my originals have lost the tweeter output. I tested the tweeter and all is good. This particularul 15ohm Xover has a history of one of the resistors getting too hot and indeed, a visual shows some good darkening of the PCB as it rests just on top.
I swapped out the Xovers and all is good so how does one test a Xover without ruining the original from a value perspective? AND, without disconnecting a single leg of any passive component? any secrets?

P.S. I have yet to measure the difference in ohms between both Xovers from outside the cab but i imagine they wont be the same.
So I can measure across the resistor without pulling a leg or two?
diyAudio Moderator
Joined 2008
Paid Member
Each may have different effects. If L3 or R3 is shorted you may have a problem. At most you'd measure the resistance of the coil so it will be close. Compare to the internal meter resistance to be sure.

For that we need to know what the meter reads for resistance when..
1. Shorted,
2. Across R3.
Last edited:
diyAudio Moderator
Joined 2008
Paid Member
Normally.. Well, you could measure C4 as open without removing it, you could measure R3 as shorted but you couldn't measure it as open. So each one depends. On the other hand there's more than one way to measure, say, if you could run a signal throught it.

If unsure, lifting only one leg is enough.