Nope... unless the differences below are product variances in the used driver
K702 with K712 pads vs
K712
There definitely is a 'family resemblance' in the drivers though, just like there is family resemblance in HD600 and HD650 drivers.
I found about 2dB difference between
worn pads and
new pads (on HD650)
Below pad compression on
HD660S2 (compression of new pads is not the same as aged foam though)
About 3dB difference here but the pads were compressed about by 9mm.
B.t.w. I concur with the criticism... HD600 should have been measured with new pads.
But... the headphone that was sent in did not come with new pads and was measured as it came in.
We can't expect people that send headphones in for measurements or having Amir buy fresh pads for every used headphone that is sent in.
HD600 and HD650 do not measure nor sound nor are the same. In this review they were close simply because the pads were worn.
I also agree that most of the 'my headphone mellowed out in the treble over the years' or 'the driver finally burnt in and now the treble is softer' is often caused by pad wear (softening of the foam).