I would say that even past 9 kHz I wouldn't put too much faith in my measurements. However, below that frequency things start to match what I hear (relatively speaking). Consider the following plot comparo (measured twice a few minutes ago) between the JVC XX and the Tenore:
I compared with 1 kHz and 5 kHz sinusoidal waveforms, and I think I heard the 20 dB drop off difference between the two cans at 5 kH. Things get closer between the two at 10 kHz w the XX being louder at that frequency. In all cases I tried to match 1 kHz by ear. This was very rough since I don't have two independent headphone outputs and had to readjust at 1 kHz.
20 dB is a very noticeable difference, but it's not loud and drop dead silent different. I think I heard that difference with the tone test, but I'm definitively not golden eared or so.