PleasantSounds
Headphoneus Supremus
Ok, I see how that all works now. Thank you for the useful info! It sounds like it is almost a similar situation to tubes vs. solid state, where the distortion is tubes is what makes them sound warm, just like the less technical ability of an amp to remove "backcurrent" as you say can add a bit more bass. Both are technically engineering "flaws" but are musically correct. Interesting stuff.
Just to make one thing clear: I'm not saying there's not enough bass for me. The tonal balance is very good, bass goes really deep and is never weak. But I'm not used to the low notes ending so abruptly. Maybe it's me, maybe it's the recordings...