Death vocals are a deep, raspy way of singing, characteristic for death metal, but also often used in other genres. They are also known as growl vocals.
The "blasphemous" lyrics don't bother me, the chaotic music doesn't bother me, and the growled vocals certainly don't bother me. Detractors complain that they can't understand what is being said.
A mistake that most death novices make is growling through their throat.
Delivering deathvocals requires a great deal of energy, and drugs of any sort will only emasculate your staying power.
Death-metalvocalizing is also known as Cookie Monster singing, if not in tribute to, at least in acknowledgment of, the "Sesame Street" puppet that blurts in a guttural growl, his words discharged so rapidly that they tend to collide with each other.
But while the vocals in early death metal are low, raspy and aggressive, not unlike the vocals by, say, Lemmy Kilmister of Motörhead, that extreme degree of Cookieness is missing.
She does vocal exercises to keep fit, some of which she learned from Melissa Cross, a New York-based voice teacher whose instructional DVD "The Zen of Screaming" is a favorite of extreme vocalists.