TWEETERS! Hi - It's me again - just thought I'd post this little update since, believe it or not, I still get private emails about Dahlquists from this thread.
My 4 year old son recently blew up one of my DQ-20i tweeters and I had to replace them. The originals were Scan-Speak Type D2008 Code 8517. The drop in replacement which is available at Madisound and elsewhere is the Scan-Speak type D2008 Code 8512. Since there is a difference in codes I called Scan Speak in Denmark and spoke to an engineer there. He could not find any info/records on the 8517, but assured me that the D2008 would be a sonic match.
Well, after soldering them in (very easy job) I can tell you - I wish my son had been born sooner! :) The new tweeters were a very noticeable improvement over the pre-blown old tweeters. Whether the old ones were already beat and on their way out anyway, or the new ones are just better - no way to know. But yours are probably in the same state - and this is a VERY big improvement. Bottom line - if you have a pair of DQ's, I STRONGLY recommend replacing your tweeters with these. Especially since you never know when the D2008 will go completely out of production. Of course, keep the old ones as spares, too.
It's a simple job. Remove the back cage and front grill, Unsolder old ones, unscrew the old tweeters, replace and solder new ones. Whole thing should take less than an hour. The only caveat, of course, is always with tweeters don't overheat with the iron. Just do it accurately and gingerly. If you need to change after the first try, let it cool, remove, cool, then redo.