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B&W CDM- bad crossover????

I have a pair of B&W CDMs that I bought on ebay a year ago.  I tend to buy speakers I don't need and felt I got a good deal.  After about 6 months or so, I finally got around to hooking them up.  There is hardly any high frequency output.  At first I thought the tweeters were fried, so I found some replacements from Madisound or PartsExpress.

It was a relatively simple job, but they sound exactly the same.  So now I'm thinking both the crossovers have issues.  Any advice on how to proceed would be helpful.

Of course the seller stated they worked perfectly when he had them.  He used them as surround speakers and wanted to sell them after he torched them or they stopped functioning properly.
dastro
dastro OP
42 posts
 
Not dumb, but yes, they are in place.  I've also tried bi-wiring.
czarivey
5,740 posts
 
Crossovers are very easily diagnosed and repaired.
There are few elements need to be tested basically, but large load resistor, if present needs be tested first. 

dhl93449
455 posts
 
See if you can get the service manual from B&W. They have them for the discontinued models on their website.

If the crossover is typical of most B&W designs, there is a single coupling cap connecting the tweeter to the input. There may also be a resistor in series with the coupling cap (but not always). So either one of these may be bad. I would temporarily jumper (short out) these two components to see if you have high frequencies, but do it at low volumes! It would be strange that BOTH speakers would have the same defect, however. You might also check the wiring to be sure everything is connected as it should be, particularly the wire connectors to the crossover boards
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