OK test performed in the following highly unscientific manner:
1. Set both headphones to high-comfortable listening level
2. Press earcups together of both headphone and hold at arm's length.
3. Move arms until headphones sound about the same volume.
Now here's something interesting: with active noise cancelling off, the Goldrings leak less than the JVCs. With it on - they leak more - quite a bit more - as in the volume sounds about the same for a full arm's length as the JVCs do for half an arm. I note that the Goldrings sound signature changes with ANR on - the mids and treble become more prominent and the base tightens. It becomes less but faster and punchier.
With both headphone set to a low-comfortable listening level they are almost inaudible at arms length.
My opinion on respective audio quality is unchanged. The Goldrings are more accurate, more revealing, have tighter & punchier (but a little less) bass, better instrument separation etc. They are a heck of a lot harder to drive in passive mode than the JVCs though. They do need an amp for passive mode.