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Interestingly Genelec, up until recently at least - I have not checked lately - followed the guidance of the ISO and EBU standards (they are the same) because of their business with the broadcast industry. In brief, these standards require loudspeakers with anechoic (1/3 octave smoothed) on axis responses that are flat within +/- 2dB. OK. But then they tell users to measure steady-state in-room curves and adjust as necessary to make them flat (with a large tolerance). Unless one is listening in a non-reflective environment, or extremely close to the speaker, one cannot have both. There are more shortcomings of the standards, but this is a very bad start. In normally reflective rooms the steady-state room curve from well designed, neutral, loudspeakers will tilt downwards - they are flat and smooth on axis as measured in an anechoic space.
This emphasis on steady-state room curves above the transition frequency is wrong - it is a poor correlate of sound quality. My JAES paper cited in the first post in this thread explains, as does my book. It is embarrassing to look at the performances of some "reference" pro monitor loudspeakers over the years. Several spinoramas are shown in my book, especially Chapter 18.
Dr. Toole, I've just read the EBU document (https://tech.ebu.ch/docs/tech/tech3276.pdf) and I see indeed guidelines for monitor (anechoic) frequency response tolerances, directivity guidelines, loudspeaker positioning, room treatment etc. They give an 'operational room curve example' and guidelines but there appears to be quite some tolerance to this, which would still allow, if I interpret the document correctly, the natural response of whatever a "good" loudspeaker does naturally in a treated room above the transition frequency. In fact in the notes of the operational room curve it states:
To avoid degrading the quality of reproduction, electrical equalization should be used carefully. It is advisable to make the corrections in the low–frequency range (f < 300 Hz) only.
Follow by a "All channels should be adjusted in the same way." .. I hope they mean adjusted to the same target ,below 300Hz.