Low frequency

His wand emits a vibration so deep, the sound seems to echo in his ears. The air around him seemed to tremble causing a painful pressure on his ears. Harry lifted his arms in an attempt to shield his ears from whatever he had done, the simple motion of raising his arms felt as though he was trying to rip them out of setting concrete.

Harry struggled to press his hands against his ears, the frequency of the sound threatening to make his brain explode. The vibrations stopped suddenly throwing Harry roughly to the ground, he rubbed his ears sitting up slowly. Everything around him felt...odd, like he was submerged in pudding, as odd as it was it was much more manageable than the sounds. He looked down at his wand and made a mental note to wear earplugs next time.

Taking a moment to survey his surroundings, he noticed how painfully quiet it was, no wind, no birds...Harry looked up to the sky and saw Buckbeak the griffin frozen in mid flight!!

A satisfied smile stretched across Harry’s face as he thought about all of the uses this spell could have.