Super cool vid of the Osage Bass. Good look inside the back of it at the old boards. I'm sure this footage has been posted before but I just saw it and thought I'd share.The bass shots start at 3:10.
 

Can't do youtube but I'm guessing this'll be the footage from the Grateful dead movie. It's well worth getting hold of the whole thing - there's some excellent band footage and it gives a real insight into the Deadhead phenomenon.
 
Graeme

Yes ,______this is  footage from the movie. The fellow who opened the  back of the Bass Is George . George also installed  a less expensive version of his Pluto Filters in my old Guild Starfire of which I have posted pics on this site .  Phil Lesh's fascination with the EMF interference from the movie camera motor remains to be priceless in amusement .

It sounds like his bass could have used the upgrade!

I am not aware how much of the electronics in that Bass were Alembic and how much were Pluto . The Pickups look Alembic but past that I do not know. I saw this Bass close up in person as well in progress.

Looks like it has a narrow pickup very close to the bridge?
 
There's also a longer version of that clip with various people reminiscing.

Adreaan. that bass had 2 normal p/ups & 1 quadraphonic p/up; I imagine one of the four things there, either the middle or the one you reference, was the HX.
 
Peter