AR tweeter assembly and adhesive??

[Guest audioslave]

Does anyone know what kind of adhesive AR used to attach .75" tweeter domes to the front of the magnet, mainly the tweeters used in the 3a, 5, LST, LST-2 and the later 2ax,? The adhesive is clear and rubbery, like silicone or even rubber cement. Also, any clue to what the red, foam like substance is that's spaced 120 degrees apart?

I've disassembled 3 out of 6 open LST-2 tweeters. One was an immediate casualty for the coil stayed in the gap as the dome/former was removed. The other two were dissected successfully. Both were open right before the wire curves upward on the former towards the dome. I was able to unwind the voice coil one turn and restore continuity. Both are playing and measure 5.6 and 5.9 ohms.

Any input on reassembly is appreciated!

Jeff

[tysontom]

There are two substances used in the 3/4-inch tweeter (as in the AR-3 midrange and tweeter). The foam pieces, equally spaced in three areas in slots on the top plate (not the magnet itself), are urethane foam (two part poured in as a liquid that turns into foam) and butyl-rubber or liquid latex poured around the diameter of the dome.

The butyl-rubber compound has nothing to do with the suspension, but is there to protect the voice coil from dirt and contamination. It is clear and elastic. The three foam pieces actually are the suspension system for the dome itself.

--Tom Tyson

[Guest audioslave]

Thanks Tom!!!!

Will the foam that is attached to the pole piece insure proper height when I reset the dome, or was it just used for dampening?

Has anyone tried this before and had any succsess? My fear is that, by unwinding the voice coil one turn I will have changed the sound of the driver too much.