I've just picked up a fault in the AE-35 unit."

He did an awesome job as Hal, but didn't like the notoriety that came with it.

I suppose they wanted a voice that was recognizably human, but otherwise cold, rational, and dispassionate. Although even a character within the film itself lampshades this by pointing out the sense of pride he gets from HAL when HAL explains the fault-free history of the 9000 series computer.

Douglas Rain was a wonderful choice. And who could now imagine anyone else providing the voice for HAL?

Personally, I found the voice polite, cheerful, and companionable. And it reinforced my belief that HAL9000 was the hero, not the villain, of the film.

was the perfect voice for Hal, so human. Compare it to the robotic enhanced voice of Paul Frees in Colossus The Forbin Project (1970).