Jimmy Savile's former BBC radio colleague Paul Gambaccini claimed on Tuesday it was known among staff that the late presenter targeted vulnerable, "institutionalised" young people.
And he alluded to claims Savile had been involved in "necrophilia" and questioned why newspapers had failed to run stories about suspicions while he was alive.
Gambaccini worked with Savile at Radio 1 where he had first heard stories about his abuse of under-age girls.
He told Radio 5 Live presenter Nicky Campbell on Tuesday that he used a "politically incorrect" term to categorise the people to whom Savile devoted his attentions.
"The expression I came to associate with Savile's sexual partners was either one used by production assistants or one I made up to summarise their reports ... 'under-age subnormals'," said Gambaccini.
"He targeted the institutionalised, the hospitalised - and this was known. Why did Jimmy go to hospitals? That's where the patients were."
But he said these things were taking place at a time when staff failed to get to grips with the concept of paedophilia.
"It was considered so far beyond the pale that people didn't believe it happened," he said during the 5 Live Breakfast Show.
And he said the problems with failing to call Savile to account went well beyond the BBC.
He questioned why newspapers had not acted when he said a tabloid reporter had boasted that his colleagues were aware of a story linking Savile to "necrophilia".
Campbell pointed out: "That particularly lurid accusation that you have just brought to people's attention is one that has not been in the public domain."
Gambaccini agreed and asked "why not?" And he asked: "Who vetted the knighthood? Coco the clown?"
He said the entire society was taken in by Savile - "including the prime minister who invited him to Chequers; including the royal family, photographed with him, he got a knighthood in this country, he got a papal knighthood.
"This is not just the BBC this is history, this is a man who conned an entire society," Gambaccini added.
It came as the BBC Director General George Entwistle was accused by MPs of failing to "get a grip" and compared to James Murdoch during a stormy select committee session in the wake of the Savile sex abuse allegations, after which the culture secretary said the scandal raised "very real concerns" about public trust in the BBC.
In a letter to Lord Patten, the chairman of the BBC Trust, Maria Miller said: "Following today's select committee hearing and the revelations that have emerged about the factual inaccuracies in the BBC's explanation about why the Savile item in Newsnight was pulled, very real concerns are being raised about public trust and confidence in the BBC.
"In all our conversations we have talked about the paramount importance of full public trust in the BBC's inquiries and agreed that it is essential that licence fee payers can be assured that they are being conducted thoroughly and with the full cooperation of the BBC, in line with the Trust's duty to 'ensure that the BBC observes high standards of openness and transparency'."
Ms Miller said it was "vital that these inquiries are able to follow the evidence wherever it takes them" and welcomed Lord Patten's "commitment" that would happen.
In a letter responding to Mrs Miller tonight, Lord Patten wrote: "You know how seriously the Trust takes the allegations surrounding Jimmy Savile and the need to maintain public trust in the BBC."
He said the inquiries would be "comprehensive and independent", adding: "You have recognised both the credibility and the scope of those who are leading the inquiries and the wide scope of their terms of reference."
But the peer also delivered a thinly-veiled warning that the government should not wade into the row.
"I know that you will not want to give any impression that you are questioning the independence of the BBC," he wrote.