Simplify the following text for a Grade 11 native English-speaking person.
Original: Shown in the season 2 DVD special feature `` Confidential Cut Downs , '' the voice was created by processing Brigg 's voice through a voice modulator .
Simplified: As shown in the second series of Doctor Who Confidential , the timbre was created by processing Brigg 's voice through a Moog moogerfooger ring modulator .