Here we go... - Remember I'm still a n00b in measurements. so take that with the usual caution. - I posted my measurements rig in the dedicated post. - That's raw measurements without any compensation. - Do not compare this with other measurements. HD800S FR Left and Right HD800S FR compared to HD800 Stock, modded*. I give HD600 FR as benchmark *my HD800 was modded with a ring of felt/foam around the driver and some rugliner over the Grey Mesh. HD800S Waterfall Plot HD800 Waterfall Plot for comparison HD800S Spectrogram HD800 Spectrogram for comparison HD800S distorsion.