I think the actual "effect" you're looking for is achieved by closing the throat ... just a bit, and pushing the air from lower in your throat. Wind players (like myself) learn to support the air flow with a contraction of our diaphragm muscle. It's hard to explain, but think of the feeling you get in your lower abdomen when you're constipated, and trying to push out ... well, you know.💩(sorry, not trying to be gross)
When done correctly, using supported air, and not just volume, it is not damaging, and can be controlled quite easily.
I've said many times that the best vocal lessons I ever learned were actually techniques from playing woodwind instruments. Clarinet, sax, flute etc ... all gave me valuable breath control, and stamina that I might not have had otherwise.

Try this ... open your mouth (a normal distance) and sing the syllable "Ahhhhh" ... gradually lower the intensity of your air flow, and start to close off your throat. You should hear that "Growl" start to emerge. Experiment with adding different sounds, words etc, and see if you can grasp the concept. How this helps.
BTW:
The sax growl, in a real instrument is actually achieved by rolling the tongue, like a long RRRRRR-type sound. It forces the air to travel quicker, and the reed vibrates in a more unpredictable pattern.

If you want to learn about some important logopedic facts for variation of singing, this video is helpful:

Not the right way, but drinking too much, staying up all night
and screaming your lungs out does work...BELIEVE ME!


Russ

But you have to start doing that when you are young ...

Very interesting topic Mark, I wish I had an answer. I do ponder this often though.

I agree with Tony, that Elvis had both a great smooth voice and a great rock voice. That made him unique for sure. I think Linda Ronstatd also had an amazing and versatile voice too.

It’s seems very few can sing equally well with either a clear or gritty voice .

Good well thought out replies....and....sensible....don't DAMAGE the vocal chords!

I even watched the video that CROSSOVER posted. As Charlie Chan once said.....verrrry verrrry in-ta-rest-ing!!!

I suppose I didn't say the question correctly. I didn't so much mean "strain my voice"....I meant "process my voice" with today's modern technology. Take out the "highs" or the "lows" or do whatever they do in a studio to change the voice.

A great example (among many great examples) is Ian Gillan-lead singer for Deep Purple. I mean, I could never sing like THAT but the sound of his voice has been electronically processed. Are my correct?:



Would you believe....look at what I just found!

As I said, I can get a 'growl' for a word or two, and at today's gig (job) at a really nice AL/IL venue ( I wish I could afford) I did it a couple of times on different songs... as I was packing up, a fellow came up to me and said I should sing "What a Wonderful World" like Louis Armstrong ...
I didn't have the heart to tell him that isn't going to happen ...