Black triangle/lights formation in triangle shape sighting with soundWhile I was watching the stars through a broken cloud cover, I saw a black triangle craft for a split second. I had watched it for 3-4 sec to realize it was a black (air)/ship/craft/thing (not stars) flying over a broken sky.To my amazement, it was a typical V shape, more like a Christmas tree V shape, rather than a B2 stealth bomber. It was more like two converging rows of lights in a V formation, moving swiftly over the entire sky in mere seconds. A few second later, a subtle low hum, much like a jet at high altitude, the way you would ear it on a quiet farm.After thoughts: I saw it right above me, between two low clouds. Altitude was IMO, for a craft the size of a Airbus 320, around 6 thousands feet, and with speed over mach 1, (really quietly), north bound. The sound could not have been another high altitude jet, cause we can hear many every -quiet- day. I remember my surprise to ear such a low and distorted sound. Much like one of a quiet multi engine jet...End report.I think it is ours. And I would hope, the US navy's skunk works.Because if it's not ours, it makes noise and doesn't look so exotic, like a silent disk. But then, is a noisy triangle more human or terrestrial?