Any recommendations for a portable headphone amp and/or a desktop amp in the $100-$200 price range? Obviously, if it's slightly over $200 that's fine too.    I have the 80ohm version of the 770s and seems like I have to just about max out the volume on both my computer and iphone to get the...

Is there any place that carries a good assortment of headphones that you can listen to? Tried Guitar Center and Best Buy but both were a bust. Guitar Center did persuade me into the Beyer DT 770s and I'm super glad they did, but would still love to keep looking for the "holy grail" of...