Your claim - HD650 has more treble than HD800S
So far
everyone has disagreed, including producing graphs which prove it. The 2 Sonarworks graphs overlaid on each other (below). I'm not sure what you're not comprehending with this .... green is the HD800S. Lower treble is generally held at about 6-10 kHz. HD800S has more treble in this area. Upper treble is above 10 kHz - HD800S has far more treble in this area. If you're talking about that tiny little bit of blue at 18 kHz or so - good luck hearing that in actual music.
You're welcome to state what you think you hear. All I'm saying is that actual measurements don't agree with you.