From Dragon Ball Encyclopedia, the ''Dragon Ball'' wiki
Yūsuke Numata (沼田 祐介, Numata Yūsuke) (born on June 10, 1968 in Kanagawa, Japan) is a Japanese voice actor and affiliated with Aoni Production.
He was the voice of Ikose, Jewel, and the Saibaimen in the Japanese dub of Dragon Ball Z, Baby in Dragon Ball GT, Gregory in Dragon Ball Kai, and Abo in Dragon Ball: Ossu! Kaette Kita Son Gokū to Nakama-tachi!!