Well, this thread wouldn't really interest me if it wasn't for Wishin and I "making a trade" last year.
When the DuoJet hit my place, it was a new toy, and time to play it and start "fine tuning".
Wishin's observations are the same as mine with the spacers installed. My bridge pup gets "nastier" now, and both pups just have more "beef".
I've listened to the clips several times tonight, and I have to say that stock Dynas, with spacers, are doing the trick for me, based on what I'm getting out of the clips.
Maybe I was expecting a bigger difference than the clips are revealing. I've experienced the ceramic Filter vs TV Classic improvement, and it was a very notable improvement to my ears.
The SD's are different, but they are not making me say OMG!
Right now, if I were to lay out $450 for a pair of anyone's pups, I would really want to say OMG, WHAT a difference.
I'm not hearing it today.
Edit: Tom, my Duo is an '06 "JT" with reasonably thick plastic spacers on both pups.
I raised the top of the neck pup to sit almost equal to the fretboard level. I did this based on pics from Paul, and a few others on the board.
Most shots of vintage Jets have the pups "right up there", so I thought that I would give it a try.
I adjusted each pole piece down, down, down, until things didn't sound right, and then started raising them to hit that sweet spot.
One string at a time, one pup at a time, and tried to get the most "even" sound for a good string balance on chords.