The recent arrival of a son & heir - six weeks old and full of life - has necessitated more headphone listening. A small price to pay for such wonderment. (No more gushing, I promise!). Just this very evening I have been giving the new Zep compilation* a blast through my Sennheiser 600's connected to my Arcam A85 amp's headphone socket. Changing listening mode for when I walked the dog, to PX100 headphones into my iPod, I was surprised to notice how little difference there was in what I was hearing. So, I'd like to know how can I improve my hi-fi headphone listening. I've read with great interest recent-ish postings about heaphone amps and headphones; any advice anyone? * fantastic remastering job. I was giddy with the sheer thrill of familiar tracks heard anew. Particularly when I rakishly slung the 'phones to one side for 10 minutes and let Achilles Last Stand resound untethered through the whole of my system.