u/PatientMasterKiller

Hello, currently im in the process of making my cosplay/costume for mcm london in may but currently im struggling to find any good videos or suggestions as to what voice amplifier/changer to use to sound like Moff Gideon(I dont mean his voice specifically)
https://www.youtube.com/watch?v=rPIBgV-vydM
Im trying to find something that sounds like his helmet but so far ive found next to zilch, any help/suggestions would be appreciated : ).