Masao Nakasone (中曽根雅夫 Nakasone Masao) was a Japanese actor and voice actor. He was one of the three voice actors that voiced the titular character of the Ultraman. Due to this, his grunt for Ultraman, "Shuwatch!" (シュワッチ！ Shuwacchi!), had always being frequently used in most of the Ultra's appearances in the series.
Around September 2, 1993, 3:00 pm, he was found dead at his own house. It was Nobuo Tanaka, a fellow voice actor that called the police after he found Masao's dead body at his house. The cause of his death was theorized due to being under depression, as he had divorced with his wife and separated from his family.
Nobuo Tanaka talked about the situation at the time of his death, "September 2, 1993, 3 o'clock" (Nobuo got a note from the police that found Masao's dead, took notes and memorized it, this day is [Deathday] ,unconfirmed). "Fainting cold, weak death or disease death" is stated. The police inquired to Nobuo said that the name of Nobuo was written in the handbook of the article and the reason was that the house was also a neighborhood. However, Nobuo said that he did not even know that Masao lived in the neighborhood.
Nobuo Tanaka recalls about Masao Nakasone, "Although he was a coward, he was a kind man that was too tender." He said that he wanted to return to Nobuo as an actor just before his death..
- Ultraseven - voice of Ultraseven in some grunts (TNT/TPS/Cinar English Dub)
- Ultra Fight - voices of Ultraman and Ultraseven in grunts
- Return of Ultraman - voices of Ultraman Jack, Ultraman and Ultraseven in grunts
- Ultraman Ace - voices of Ultraman Ace, Zoffy, Ultraman, Ultraseven and Ultraman Jack in grunts, Father of Ultra in deep-voiced grunts in episode 27
- Ultraman Story - voices of Zoffy, Ultraman, Ultraman Jack and Ultraman Ace in grunts
- Ultraman: Towards the Future - voice of Ultraman Great in grunts (Japanese Dub)
- Ultraman: The Ultimate Hero - voice of Ultraman Powered in grunts (Japanese Dub)
- Ultraman Neos Pilot Episode - voice of Ultraman Neos in grunts
- Ultraman Tiga - voice of Ultraman in grunts
- Ultraman Mebius - voice of Ultraman in grunts
- Ultraman Mebius & the Ultra Brothers - voices of Ultraman, Ultraman Jack and Ultraman Ace in grunts
- Ultraman Mebius Gaiden: Hikari Saga - voices of Ultraman, Zoffy, Ultraman Jack and Ultraman Ace in grunts
- Great Decisive Battle! The Super 8 Ultra Brothers - voices of Ultraman and Ultraman Jack in grunts
- Ultra Galaxy Mega Monster Battle - voice of Ultraman in grunts
- Ultra Galaxy Mega Monster Battle: Never Ending Odyssey - voice of Ultraman in grunts
- Ultraman Ginga - voices of Ultraman, Zoffy, Ultraman Jack and Ultraman Ace in grunts
- Ultraman Ginga S - voices of Ultraman, Zoffy, Ultraman Jack and Ultraman Ace in grunts
- The・Ultraman: Jackal vs. Ultraman - voices of Ultraman, Zoffy, Ultraman Jack and Ultraman Ace in grunts
- Ultraman X The Movie: Here He Comes! Our Ultraman - voice of Ultraman in grunts
- Ultraman Orb - voices of Ultraman, Ultraman Jack and Zoffy in grunts
- Ultraman Zero: The Chronicle - voices of Ultraman, Zoffy, Ultraman Jack, Ultraman Ace, Father of Ultra, Ultraman Great, Ultraman Powered and Ultraman King in grunts
- Ultraman Geed - voices of Ultraman, Father of Ultra and Ultraman King in grunts
- Ultraman Trigger: New Generation Tiga - voices of Ultraman in grunts
- According to Hajime Tsuburaya, Masao Nakasone was meant to be the voice actor for Ultraman (both of speaking voice and grunts) but due to his absence at that time for unknown reasons, he was unable to do so. Therefore, Hisashi Kondo took the role as Ultraman's speaking voice. However, Ultraman's grunts are still made by Masao.
- According to Toshihiro Iijima, one of the directors of Ultraman, after they had Ultraman's design, they chose Masao Nakasone to do some grunts for him. After completing the voice, they mixed a bunch of those together and got "Shuwatch". However, in reality, Ultraman actually shouted "Shwa" in many first episodes instead but later they added "ch" sound at the end to make a clear "Shuwatch".
- Masao Nakasone shares a few similarities with Saburo Shinoda, the first voice actor of Ultraman Taro:
- Both only reprise two different roles on the Ultraman Series, one of them is their noticeable role (Ultraman's and Ultraman Taro's voice actor).
- Both are actors and voice actors.
- Both their grunts for their Ultra (Ultraman & Taro) are still kept and reused in the later appearances
- However, unlike Masao, Saburo is still alive and did not retire yet.