My solder tips are too big....LOL. Seriously, I am going to need the right tools for the job so I'll dust off a new soldering station I purchased a while back and see what I have. That's a good pointer...thanks!
You raise a great point about stress relief which, surprisingly, I had thought about. I don't have a great answer...I was planning on using different sizes of heat shrink. So a small piece would cover any exposed wires at the butt of the plug. A larger piece would go over it and hopefully fit over the Koss cable or at least to the very edge (I may need to leave some of the internal sheathing on the individual wires aft the end of the rectangular mother cable...I'm sure my nomenclature is shite...sorry). Finally, a big arse piece of heat shrink for the crap metal knock-off Stax plug down to the Koss cable. So layering if you will. I figure that will be pretty damn stiff and while not great, hopefully it will provide some protection.
In the end, if I buger this up good which is a distinct possibility, I buy one of these pricey cables from Fong audio or Apuresound (which may have a bad rep...dunno).
http://www.amazon.com/Koss-ESP-950-5-pin-Adapter-Cable/dp/B00LCKWG40
http://apuresound.com/images/cables/electrostatic/950/index2.html
HS