What do you know about the JENSZEN Z-600 speakers and cross-overs


I have a what looks like a perfect pair of these Z-600 speakers , but they almost sound like the cross-overs are messed up........They seem to be lifeless in sound, light in the bass, no real detail.....Maybe a past engineer could help me sort this out.........THANKS
autospec
I don't have a ton of experience with these, Its been many years These speakers require some real current to come alive.  They are a difficult load and not many tubes will run them.  
Not sure this helps, but it is what I recall. 
Tim 
I assume you meant Janszen Z-600.  If so, the company is again in business and David Janszen is familiar with all of his father's designs.  I'd suggest contacting him with your questions.