To make a long story short, do not make a full judgement about these headphones until they are full broken in, and do not overlook the difference an good headphone amp will make

Electric bass through a tube amp sounds like electric bass though a tube amp, not enveloping, room-shaking bass or amorphous blobs of low frequencies

In order to get the most out of the SR325e headphones, or any of the Grado headphones, a good headphone amp is required

The SR225e's have a slightly gritty sound on the high end when listening through a high quality solid state amp, which lends itself well to live music - especially rock

With these cans, a decent DAC, and amp you can truly hear the nuance you've never noticed buried in tracks you've heard a thousand times

A DEDICATED DAC/AMP

An amp is not necessary with these cans, but it can't hurt

Pretty much everything, from the grinding of a bow on cello strings to the breathing of pianists and artifact noise on small audio files, all bloom as if someone just put them there afterward, and loud and soft sounds suddenly give music a more rollercoaster-like experience