I was wondering something similar.
DPA makes extension cables for the 406x's. I'd like to make an adapter where I would take the female end of the extension, then cut off the other ends and turn them into a 1/8" stereo plug so I can use my 4060's with the MMA6000 or also convert them so I can run them directly into a R-9 (for those extra stealthy situations).
Does anyone know if that is possible?
Maybe the two of us could split that cable. I would need one half and you might be able to use the other end with a female 1/8" plug.
Here's a pic of the cable: