The spring rates are higher, dampening is stiffer, and there's more insulation to protect from pesky noise pollution in the cabin, so that all you're liable to hear is the pleasing low growl of the tuned exhaust. (nydailynews.com)
The darkened room filled with low growls and maniacal cackles, and marine biologist Adam Ratner asked the children, «What animal is this?» (marinemammalcenter.org)
At the shelter, he was hiding inside his crate and did low growl when cornered. (furryfriendsrescue.org)