Am i benefited from using a headphone amp ?

ttboy,
there is no doubt in my mind you would recognize a superior level of musical satisfaction with the use of a headphone amp!
there are many, both tube based and s.s. to choose from, some with built -in dacs ranging from just under your pricepoint to several thousand.
check first to see if you need all the "bells and whistles" that are offered then goggle "headphone amps" and you will find many companies to review.
good luck!
azjake
p.s. there are several good "used" models out there at reasonable prices too!

Do some research at www.head-fi.org.

(Sorry about your wallet.)

I was in the same boat as you are with exactly same amout to spend on a headphone amp to drive the Sennheiser HD580.

Here is my story.......

http://www.audioasylum.com/cgi/m.pl?forum=amp&n=75506&review=1