A former teacher and choirmaster, who is also a musician and had worked on TV and film projects including Wallace and Gromit, has been jailed for 12 years for child sex offences concerning 19 victims and spanning more than 40 years.

David Pickthall was made an MBE in the Queen’s Birthday Honours List in 2015 for his services to education and charity, and had worked on a number of TV and film projects.

A since-deleted online biography detailing his career achievements noted that he was the “musical voice” of villainous penguin Feathers McGraw in the 1993 short film Wallace And Gromit: The Wrong Trousers.

The 66-year-old, of Ingrave Road, Brentwood, Essex, also worked on the post-apocalyptic horror film 28 Days Later and with a number of philharmonic orchestras.

Judge Mary Loram KC, sentencing at Chelmsford Crown Court, told Pickthall: “You are without a shadow of a doubt a predatory and manipulative paedophile who has adapted his offending over the years.”

She added: “If you hadn’t been arrested you would have carried on.”

The judge sentenced Pickthall to 12 years in prison, with a four-year extended licence period, and also made him subject of a sexual harm prevention order.

The defendant, who glared at the judge during sentencing, slowly put his jacket on afterwards before he was led to the cells.

He had admitted at an earlier hearing at Colchester Magistrates’ Court to 29 child sex offences concerning 19 people and spanning more than 40 years.

The crimes were committed between 1980 and 2021 in Brentwood in Essex and Upminster in east London.

The court’s public gallery was filled with victims and their supporters who came to see Pickthall face justice.

The judge said, before she began sentencing, that “there can be no sentence that will ever adequately reflect their (the victims’) experiences”, adding: “It’s not a quantification of their distress.”

Fiona Ryan, prosecuting at Monday’s hearing, said Pickthall had admitted a “range of predatory sexual offences, primarily committed against students and former students of his at Brentwood School”.

She said that “secretly he had a penchant for touching and spying on young adolescent boys and his desires were easily satisfied because of the positions he held”.

The barrister said Pickthall would sexually assault boys “under the pretence it was part of the teaching style” and would “begin by tickling them under the guise of a mild punishment for getting something wrong”.

He would progress to put his hands into their underwear, Ms Ryan said, adding that he gave students alcohol when they visited his home.

Pickthall would encourage students to stay in “what he called his guest suite”, the prosecutor said, and he kept pornography there.

A student found a concealed video camera there, she said, which Pickthall recorded visitors with.

“He (Pickthall) selected and retained some of the most intimate images for his own sexual gratification,” Ms Ryan said.

She said that in 2021, Pickthall used a fake social media profile – “pretending to be 17 initially” – and kept asking an underage boy for a photograph of his penis, which the boy eventually sent.

One of his victims, who cannot be named for legal reasons and who was given the pseudonym Mark, said ahead of sentencing that Pickthall abused him from around the age of 12.

Mark, who is now aged in his 50s, said Pickthall – who had taught him music – groomed him and began to touch him inappropriately.

He said this went on for around four years.

“At the time the physical and the sexual side of it was really unpleasant but that isn’t what stuck with me,” said Mark.

“I would say that 90% of the damage he did to me was psychological.

“One of the things he said to me, and it will always just haunt me forever, is that… he said to me ‘nobody will ever find you attractive or love you and you should be grateful for the physical attention I’m giving you because no-one else will give that to you’.”

He said he went to the police in 2021 as it was the “right thing to do that I should speak up about it and hopefully stop any other children or their parents being put through this ordeal”.

Mark said that at the time he did not think he would have been believed.

“Pickthall clearly had two very distinct lives,” he said.

“In the public eye he was a well-respected teacher, he was an accomplished musician, he delivered concerts, he’s written scores for household names like Tracy Beaker, Julian Fellowes, Paul O’Grady.

“I can always remember that when I went to concerts where he was performing he would quite often be the conductor at those concerts and at the end of the concerts the audience would give him rapturous applause.

“There would be a standing ovation and he was stood there literally basking in this adoration of him.

“I found that really difficult to deal with as I knew that behind closed doors he was a monster.

“He created this aura that he was really well-respected, he had been given awards for his commitments to charity, education, he even got an MBE from the late Queen Elizabeth.

“The fact he could create this public perception of himself just to hide what he was doing privately is very difficult to deal with.”

Pickthall had admitted to 16 counts of indecent assault, 10 counts of voyeurism and three counts of making an indecent image of a child.

Eve George, mitigating, said Pickthall “did see the good sense in pleading guilty at the earliest opportunity”.

She added: “Perhaps the greatest punishment is his fall from grace.”

Ms George read a statement written by Pickthall, which said he was “profoundly sorry and deeply ashamed of myself”.

The judge said she had read Pickthall’s letter “with some amazement”, adding: “I don’t know how any of the boys – now men – feel about hearing the repeated abuse that they were subjected to as students referred to as ‘inappropriate interactions’.”