I'm pretty sure we didn't talk about growl 10 years ago, just about positive it wasn't mentioned 15 years ago. Nowadays all kinds of musical products are marketed that address growl in some way, from guitar pickups pickups (Gretch PUPs that have "just the right amount of growl") to bass PUPs, basses, amps, etc etc. No one ever told me that a GK head was "growling" in the 80's and 90's. Everything "growls" today. I'd love to know where this originated, where was it first printed. There are appearances of the words "bass growl" in older literature describing a dog's bark and soldiers' yells, but I can't seem to find anything before 2000 referring to instruments growling. BTW - none of my instruments have ever growled - they may have some low-mid presence with some upper-mids and sometimes even-order harmonics but they haven't before, nor will they ever growl.