Across the valley from Gangtok is Rumtek, a small village that is essentially a Tibetan monastery, founded by Tibetan monks exiled by the Chinese cultural revolution. Atypcally, it’s guarded by the army, and entering requires a passport and inner line permit.
They have a large beautifully appointed prayer hall, and the monks were sitting in four rows, chanting. The chants were punctuated by Tibetan horns, bells, and drums. The ceremony was no different from others I have seen in Tibet. I watched and listened for a long time.