The fade-in opening bass riff in Rush's Cygnus X-1. That's the Growl-O-Meter for me.
I think some people think of growl as lower-mid punch, but to me, growl is a gritty and aggressive tone across the frequency range, defnitely not quite a hi-fi squeaky clean tone.
I love that. Listen to this for growl
Or look up Roundabout. It's all in the Ric.
