I am in the process of refurbishing some old Sennheiser HD 540 Reference II cans. Put new earpads on them, this weekend. Will likely replace the cable soon, as it cuts in and out at times. I've been using them with my Sony Walkman (NWZ-A17), which I love to death. However I have to crank the volume to max to power these cans, and have come to the conclusion that I need a headphone amp. I've been looking at the Creative Soundblaster, as it's affordable and is one of the few recommended for such high impedence cans (300 ohm, I think).

Anyone care to share experience, etc?