I've listened to tens of hours of NotebookLM, and this doesn't even seem close. If someone had played his voice for me and asked if it sounded like any LLM/bot I was aware of, I would have said no. It would not have even occurred to me that they were thinking of NotebookLM.

As @crazygringo said, David's voice is lower. I think it might have some of the same harmonics, but it has some lower ones too, which make the overall sound come across as lower-pitched. I'm not using technical terminology here, so perhaps someone can jump in with the appropriate terms.

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amelius 4 hours ago | parent [-]

Probably it's what his voice sounds like to himself. Maybe he should listen to his own podcasts more.

	▲	apparent 3 hours ago \| parent [-]
		I thought about this. IIRC a person's voice sounds deeper in his own head because it reverberates in his skull. if anything, this would make David think the NotebookLM voice sound less like his (since his is already deeper, to begin with). But it's possible that a professional radio host is aware of this effect and adjusts for it when deciding if something sounds like him. Maybe he over-adjusts and thinks this is what he sounds like. As for his wife, it's possible that he speaks in a higher/friendlier register when talking to her/their kids.