What you're witnessing here is the 2nd Scene from the Epic Klingon Opera, 'u'. Performed by the Klingon Terran Research Ensemble. I'm not kidding.
The project strives to learn the ways of Klingon music through theory and practical application. The Klingon have a rich musical culture that until now has been largely overlooked by the musical establishment. The KTRE wish to bring this unique musical culture to the attention of (inter)national audiences and contribute to its legacy.
The first scene unfortunately had embedding turned off, but fear not as you can find nearly the entire opera out there through the related links!
The official site for the Klingon Terran Research Ensemble can be found here. They also provide a delightful Masters Series with such courses as 'A Warriors Guide to the Way of the Perfect Scream'. A must watch for any budding Klingon out there!
Tread lightly, as their site proudly proclaims that they are ready to do music battle. I'm not sure any of us are trained for such a battle!