I don’t own the K371 anymore. While I love the sound of it, I just find the build quality below par…and well auditory memory is very fleeting.
I did however compare the E3 with my HD620S not that long ago, and the DCA is what I would call an upgraded K371 aka Harman Target down to a t.
The HD620S is more in the vein of most Sennheisers I find in that there is more warmth in the low mids alongside a more meaty bass delivery.
I’ve often called it a ‘closedback HD650’ which is somewhat of an exaggeration, but I still feel it does the same thing in a closedback design: warm, realistic sound that pairs well with just about any genre I care to throw at it.
I find the mids and treble some of the very best I’ve heard over a closedback and I normally don’t even care for closed headphones.
Against the E3 I would go back and forth as to which one I prefered soundwise, but the all-around comfort and usability made the Sennheiser a much better choice for me.
Here is a frequency response of the E3 vs HD620S. I know you wanted a K371 comparison, but take this as an a/b against it’s better sounding big brother which is tuned very similarly. Like I mentioned earlier auditory memory is whack. One thing I can attest to though is that both comfort and build quality is significantly better over the Sennie vs the AKG
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