...No. I do however employ a "different" voice from my normal everyday talking style so IC language is distinct. I usually only make minor changes so I can have a greater selection of "voices" in case the PCs are interacting with multiple NPCs simultaneously. More often than not a "voice" is simply a change in pitch, tone, cadence, or pattern of speech. Sometimes for "really important" NPCs I will use the "bad impression" method to make sure that the NPC "voice" is truly distinct.
My "regular voice" is used exclusively for OOC speech.
Great topic for a thread! Cheers!
I lean this way also.
Most of this is mentioned in public or oral speaking, and it isn't necessary to be theater trained to use above with great effectiveness at the table. Take a minute or two privately to try.
Listen to monologues, sermons or speeches from different people. Try recording yourself reading a piece of writing you like out loud at what you feel in your usual voice, then again taking more time while maintaining a sense of naturalness to it. Then try at a more clipped, let's say, excited tone (your pitch will rise somewhat); all that can become the new baseline for a particular character.
Some people are described as being "loud" talkers. Some get told they mumble a lot. None of that requires a lot of effort to do, and it makes such a
distinction for listeners right away.
You can dash in mannerisms, such as repeating particular words or phrases. You can play the opposite tone to what listeners expect (The small, revelatory, "That's my secret, Cap. I'm always angry," from
The Avengers)
A different e.g.
When this character or creature becomes angry, rather than raising the volume in their voice, they speak at a slower pace, in a whisper.
If you happen to know local colloquialisms that the table will understand--
step on a crack, break your mother's back, my uncle always said-- pepper speech with those if you feel like they will fit.
Even in person at the table, if you're seated, it's possible to incorporate just the
tiny amount of body movement to signal things. You can sit erect, more towards the edge of your chair. You might slouch. Lean in slightly when the character wants to impart something secretive or important. Point a finger at someone when addressing them. Wave. Throw your hands up like one does when you don't get something, are in despair or exasperated (the same motion, but they all look different.)
None of above requires being able to slip effortlessly into dialect or fall back heavily on stereotypes. And because it's not as involved, it's easier make it more seamless, only when you're inclined.