Hi,
I got a BFE branded Lawo W989/1 about a week ago, I'm guessing that all W (X)89 units are interchangeable. So.. I was going pop the side off and see if pinout matched up to the TELEFUNKEN W689 PDF at kubarth's site :
http://audio.kubarth.com/rundfunk/index.cgi
I'd also be interested in any more info regarding this unit.