Some thoughts on EQ.
I tried Amir's EQ settings in JRiver:
https://www.jriver.com/
Within JRiver I can quickly enable and disable all EQ settings or just a single setting using the checkboxes in the DSP:
These aren't the settings for the HD560, but you get the idea:
View attachment 177976
Enabling and disabling the +7dB at 20Hz, Q1.0, I notice that it makes very little difference to the sound.
I looked at the Analyser while playing several bass heavy tracks; the one below is Daniel Avery:
View attachment 177975
Dispite being a track with plenty of bass, there's a substantial drop off below 40Hz. Other tracks I looked at showed similar drop off.
Therefore I wonder whether the large boost at 20Hz does much, other than likely increase distortion and reduce the headroom of the headphone drivers.