A quick synopsis of my resume. 30 years of hardcore interest and investment in hifi, instrument building, musician. I've owned many decades of home stereo equipment and have a definite preference and fondness for Vinyl.
The soundmagic e30 have proven non-fatiquing and thoroughly enjoyable.
Past headphones I've owned range from $1000 LCD, several $500-$200 of nearly every brand from the most current back through headphones from the 1980's and 90's.
Generally I have found many full size over the ear headphones disappointing and colored. Many have odd sound and/or a falsely exaggerated upper end clarity aspect that mimics high fidelity. I personally have spent (wasted) lots of money on these poorly designed headphones by companies who seemingly do not have a solid grasp on what instruments sound like in real life and so have no unwavering reference point to create musical and realistic gear.
Generally, I'd say the e30 is neutral/warm yet detailed with a pleasing full bodied sound and a moderate bass boost that varies depending on the particular pair (individual headphones vary even within a particular model)
The e30 is 'hi-fidelity' in the sense that it imparts virtually no sound signature/sound stamp of its own onto your music collection with the exception of the already mentioned bass and also a modest and enjoyable lushness of the midrange of 2 of the 7 pair I own. That being said I enjoy 5 of the 7 sets I own with the other two a bit less balanced.