Angel's Voice

Angel's Voice (天使の声, Tenshi no Koe) is a sub-species, sound-based caster type magic that allows the caster, that is, Zadkiel to change the frequency and loudness of his voice altogether; that is, every thing he says, screams or whispers is automatically converted into infrasonic sound.

Overview
The low frequency of these infra-sounds have long wavelengths, which makes it extremely easy for them to penetrate through human body. He can exactly, consciously change/alter the frequency to match any frequency he wishes. For example, he can specifically project the sound coming from his mouth at frequencies around 19 HZ, causing other's to see ghostly figures and apparitions as it's near the resonant frequency of human eyeball. Since it's infrasonic, it is undetectable by humans and most enhanced humans and as such, even a sound produced by him, having a loudness of 140 dBs would be untraceable/undetectable, though it will cause the hearers a significant amount of pain in their ears and distort the victim's ability to understand and process speech and experience some level of dizziness. When projected at 170 dB, the victim will start feeling asphyxiated as the low frequency the infra-sound (0.5-0.8 Hz), can force the victim to breathe against their will. In fact, using this, Zadkiel can actually control someone's ability to breathe by controlling their lungs; because of the resonance effect, at this point, this undetectable sound will actually be controlling their lungs. This combined with his tremendous lung capacity and ventriloquism skills; the latter literally being the ability to throw or project one's voice several meters away, allows him to project this infrasonic sound as a concentrated wave about 2 miles away/3218.69 meters; like a sound missile. An infrasonic scream from him with the loudness around 135-140dB can actually shatter reinforced glass. By projecting his infrasound in such a way that when it penetrates the human body, it makes the brain vibrate around eight cps, the sound has positive effect as it enhances — creativity, intuition, and a tendency towards extrasensory perception all increased dramatically. Because of repeated usage, every time Zadkiel speaks, this magic automatically converts it into infrasonic sound; making him unable to speak or communicate with someone. While, he can still alter the loudness and frequency, since it's infrasonic sound, Zadkiel prefers not to talk or even try to talk as it can still cause hearing loss or some form of damage to the human body.

Trivia

 * Inspired from every sonic scream, ever.