(not) blowing cheap output stages

Ive got a simple circuit that senses the insertion of a mono 1/4" by using a TRS jack with a pullup on the ring to +15. when the ring shorts to ground a relay fires to enable that input. Im sure its been done before many times. I am slightly wooried by the fact that the tip briefly touches the ring pin as you are inserting the plug. with a 30K pullup it should be safe, I think. I could use a FET and a really big pullup, but that seems like overkill. Does anyone have the opinion that this could fry a really cheesy output stage in a synth, FX box, etc? or passive guitar pickups? Im trying to think of the lamest output stage I have ever encountered...

I would suspect that any output stage destroyed by connection to reasonably low voltage d.c. through a 30k would also be damaged by cap-coupled mains voltages and ESD that would be encountered just plugging the 1/4" into most anything, so I suspect you are safe.

~Apropos: I have a patent on sensing the partial plug-in of headphones to a jack that might be carrying too-high-level signals, part of a post-facto round of securing IP for Harman after a multimedia speaker system had been shipping to Dell for a bit. Of course (to quote Chevy Chase in Spies Like Us) "I got nothing". :razz: