lowThose notes are too low for me.
low-pitchedThe low-pitched rumble of the train shook the house.
gutturalArabic contains guttural sounds that are difficult for non-Arabic speakers to say properly.
throatyShe gave a loud, throaty laugh.
gravellyThe actor is famous for his rough good looks and gravelly voice.
gruffHis loud, gruff voice frightened the neighbourhood children.
sonorousHis sonorous voice rang through the halls.
bassThe bass part is quite difficult to sing.