Peter Newman is famous for his voice work for Rankin/Bass. In "ThunderCats" he provided the voices of Tygra, Wilykat, Bengali, and Monkian. In "SilverHawks" he provided the voices of Quicksilver, Mumbo Jumbo, and Timestopper. Wikipedia
The definitive Wikipedia entry for Peter Newman. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Peter_Newman_%28actor%29