This is complicated by the human ear's variation in loudness perception over the frequency spectrum, and the effect this has on music. The stuff over 10k is typically mixed quieter than the stuff under 10k, though it doesn't sound that way. Records with lots of energy above 12-13khz tend to sound pretty awful.

https://en.wikipedia.org/wiki/Equal-loudness_contours

EDIT: also pitch is logarithmic with respect to frequency. 8khz sounds really high pitched.