I recorded myself yelling "no" and i used audacity to lower the pitch and i made it louder and added an echo then i recorded myself making a weird sound and lowered the pitch and echoed and made it louder and put then together why was this so hard to freaking type.
This is my voice recorded on my akg c-214 condenser microphone. In adobe audition i used effects>time and pitch>stretch and pitch (process), changing stretch to 83. 21% and semitones to 3. 58 to achieve a close approximation to the minions.