Zune HD + TF10s - Would an amp help?

That combo already sounds very good as it is, BUT I think an amp helps settle the TF10's. I use an iBasso D4 and I feel the TF10's are more articulate and controlled with the amp. The difference is very subtle but somehow I keep hearing it. Hope this helps

I am not helping your case here at all But what you could do is get a D4 like me so that you can use it at home as a USB DAC/Amp with your TF10's or any other cans for that matter and on special occasions (long flight, train ride etc) you could use the D4 as a portable amp for your TF10 and ZHD combo. Using it with a computer will yield a noticeable difference and it is almost worth it just because of that. Also, if you dont already have a home amp, this is a great option for you because the D4 is plenty powerful and will drive most cans with authority. I say most because you really cant expect it to fully drive something like Beyer 250 ohms, or senn 650's or akg k701's or something. 

Meh, I had them a while back and used an amp; in the end I sold the amp because it didn't really justify the price IMO. If you can get a good volume level with your dap then I don't see a reason as to why you would need it. 100 bucks? Hell sell the Triples and get some better IEMs.