I finally made my extension cable last night. I used solid core cat 5. It will not be moved around so I'm not concerned about cracking solid core. It's about 35 ft long and I noticed I had to turn up the volume a little bit on the amp. I just hope I'm not getting any degradation in sound quality. Do you guys think I did any harm?

Thanks

Harm to what?
 
Depending on the Cat5 you used, you probably added 1Ω to your headphones... Unless you used that cheap Chinese copper clad aluminium wire then you could have added 10Ω over the 35'...
 
I use a 150Ω impedance jack to hook up Low Z IEM's etc to my OTL amp and have to turn up the volume higher than without the adapter. It kills hum and that is what I was after.

 
I highly doubt that your extension would degrade sound quality unless it was not made properly. Since it is working then I'd say all is good.

O.K..Thanks for the reassurance TrollDragon.