You know, for a giddle, you can get a very competent DAC for under £30 to see if it takes you in the right direction, playing into the HiFi...
http://nwavguy.blogspot.co.uk/2011/0...02-review.html
http://www.thomann.de/gb/behringer_ucontrol_uca_202.htm
Epiphany Acoustics do an uprated USB DAC for under a ton and there's a tasty looking USB DAC/Headphone amp for well under £200 that was specifically designed to drive a wide range of top-end headphones...
For a giggle, I bought a Fiio D5 recently for £20 on Amazon. It does the basics so well, yet doesn't measure very well as a DAC or as a headpjhone amp. The behringer above is much better and if you can fine-solder, it seems the headphone amp can be souped up way beyond its humble origins..
Just providing some basic info. You're welcome to ignore it and aim higher from the start
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