Sorry to necro a thread that hasn't been posted to in 4 years, but I just got a pair of Koss PRO4AAT headphones today.
I had a few pair of RadioShack PRO 35 Titanium headphones and when they went out of business the Koss KTXPRO1 Titanium portable headphones were supposedly taking their place. After wearing out a few pair of those I decided to get a pair of the PRO4AAT Titanium full-sized headphones.
I use my Thinkpad X61 running FreeBSD as an Operating System and XMMS as my MP3 player, and is what I've using my KTXPRO1 headphones with so I hooked them up. The base was somewhat lacking and after reading that players like an Ipod might not have enough power to drive them, fired up my Pioneer SA-520 tube amp and Optimus 10 band Graphic Equalizer to try them out.
Everything I had read about them not having enough bass, mids, highs or soundstage went out the window and I'm pretty happy with them so far. They are heavier than I anticipated, but are comfortable fitting and not bad at all when kicked back in a recliner.
It takes about 24 hours for the tubes in my amp to really warm up to where they put out the sound they're supposed to, and apparently the titanium diaphragms take a few days to wear-in, so I'm looking forward to them sounding better and better over the next few days.
