In 1961 Grosse founded his own design and engineering consultancy business which became responsible for launching many patents throughout the world.

[2] A personal tragedy launched Grosse into psychical research, when his daughter Janet was killed in a motorbike accident in August 1976.

When professional ventriloquist Ray Alan visited the house and concluded that the girls were faking an allegedly "demonic" voice because they "obviously loved all the attention they got",[3] Grosse was so convinced it was of supernatural origin that he offered £1,000 to anyone who could duplicate the voice by ventriloquism or any other form of trickery.

However, Tom Flynn, a media expert for the Committee for Skeptical Inquiry examined Fontana's claims and suggested an entirely naturalistic explanation.

When this happens on a deck where both supply and take-up spindles are powered, the tape continues to feed, creating a fold.

He also made an appearance on the Channel 4 mockumentary Da Ali G Show in which he was interviewed by Sacha Baron Cohen.