system
A chat on subreddit /r/me_irl
human
why does it sound deeper in my head, I hate it
gpt
When you hear your own voice, you're partly hearing it as it's transmitted through the air and partly as it's transmitted to your ears through your throat and partly as it's transmitted to your ears through the bones of your skull.

Men have more distortion (per se) of their voices this way than women do, on average, primarily due to issues with frequency and overtones.  This is a major reason why it's so common for boys to lose much of their natural ability to sing as and after they go through puberty.  Their ability to hear their own voices accurately is reduced, and it takes training, in many cases, to adjust.  

The lower your speaking voice, in general, the greater this problem is, and the less 'correct' your voice will typically sound to you in recordings.