I planned to get these amps:
FiiO E5 Headphone Amplifier
So are you saying that an amp makes an enormous difference? I'm fairly new to headphones and this would be my first pair of expensive headphones ^_^ Think I would even notice any difference at all?
No, it's not enormous, per se. In essence, the bass is tighter and the treble becomes more controlled and detailed. To me, it's the little things that make the difference. If it's your first pair, I wouldn't worry about it until you're more seasoned. What are you playing them from?
Also, save yourself a few bucks and forgo the E5. It's junk, trust me.
I would definitely get an amp for them. I listened to them for about a year without an amp (and rated it because its so much better than anything else I'd owned), but now I can't listen to them without an amp. The best way I can describe the improvement is that everything sounds "clearer". You can really crank up the volume without the sound (especially bass) being harsh or distorted.
I'd spend a bit of money on an amp, simply because you can keep using them with better headphones you might (and almost definitely will) buy in the future. I have tried some cheap amps like the E5, and all they seem to do is boost the volume on things like my Ipod whereas better ones noticeably improve the sound quality.
Let us know what you think about your headphones and what amp you end up getting if you haven't bought one already
Hope this helps.