Can you give an example with some specific loudspeaker, measurements and recordings?
there are two types of neutrality
I imagine the flatness of the envelope (after processing) is similar. But I do not know whether @dasdoing thereafter applies a more downwards sloping target or keeps it as it is.
The typical Harman speaker "curve" is a downward slope from about 200hrz to 20k and rise from 200hrz to 20hrz. This is in listening room only. The slope varies and is not fixed or a goal.Care to supply a link to the other one?
btw this whole envelope method builds on the fact that we percieve peaks, not the dips (*). the fact that it seams to produce (smoothed) house curves close to those created by trail and error (sans bass boost) is strong evidence towards it imo. one can still aply a harman bass boost to it, just adust the envelope curve acordingly.
(*) there are papers out there studying envelope of instruments, and how the envelope is important to percieve the instrument as what it is.