This sound is from Megatron from Transformers Soundboard

Megatron is a character from the Transformers franchise created by American toy company Hasbro in 1984, based on a design by Japanese toy company Takara. The original Megatron was the leader and warlord of the Decepticons, a fictional faction of sentient self-configuring modular extraterrestrial robotic lifeforms from the planet Cybertron. He serves as nemesis of the Autobot leader Optimus Prime.