If I make no attempt to disguise my voice IRL, aren't you more likely to know who I am?
Yes I understand and did not think of that.
I would then propose something along the lines of, when disguise player speaks, there would be listen checks.
But that would be very complicated.
Case 1:
Tom is an investigator searching for Bob the criminal.
Tom has never met Bob and does not know what Bob sounds like.
Bob is disguised as "John". Bob uses an altered voice.
Tom meets Bob who is in disguise as "John" and they talk.
Tom would supposedly be none-the-wiser about the voice change.
Bob is safely disguised and evades the law.
Case 2:
Tom is an investigator searching for Jenny the criminal.
Tom has known Jenny beforehand, a frequent petty thief at the market.
Tom knows what Jenny sounds like.
Jenny is disguised as "Mary". Jenny uses an altered voice.
Tom meets Jenny who is disguised as "Mary" and they talk.
Tom who has keen ears, recognizes Jenny's voice slipping through.
Jenny is revealed and arrested.
And to implement these, would be easier done by player RP.
@Arawn, you said
no to implementing listen checks.
But do you think roleplaying vocal observance would be okay?