ABC chairman Jim Spigelman has sought to defend the national broadcaster against attacks from "conservative" critics, announcing a number of external audits to assess any bias in its reporting.

Mr Spigelman said he took complaints about bias seriously and was addressing complaints of an "alleged systematic lack of impartiality by certain [ABC] programs and content makers".

The ABC has been carrying out "external audits" on particular programs and interviews to see whether the journalists involved have demonstrated bias, Mr Spigelman said.

He said BBC journalist Andrea Wills was preparing a report to "assess the impartiality" of all ABC Radio interviews with then prime minister Kevin Rudd and then opposition leader Tony Abbott during the recent election campaign.

A second audit will consider the "treatment of the debate about asylum seekers," Mr Spigelman said.

He said he did not accept that bias was systematic, but he accepted that "it sometimes occurs". He noted that the most complained about programs tended to be the ones "which interest the political class most".

"Since my appointment I have naturally been concerned with the frequency of allegations of a lack of impartiality," Mr Spigelman said.

Under the ABC statute the board is responsible for ensuring the impartiality and accuracy of news and current affairs. Mr Spigelman said he took his statutory responsibilities "seriously".

The ABC will publish a series of "editorial audits", he said.

Mr Spigelman said he believed the allegations of ABC bias had more to do with the topics chosen for reporting, rather than their content.

"Journalists - all of you, not just you at the ABC - tend to have a social and educational background ... that make them more interested in, say, gay marriage than, say, electricity prices," he said.

While resisting naming the politicians and conservative commentators who have recently been lashing the ABC, the former NSW chief justice gave his staunchest defence of the national broadcaster since the election of the Abbott government, suggesting their arguments were bemusing and Orwellian.

"I am bemused when I notice that some critics who wish to tear down this long-lived institution call themselves 'conservative'," Mr Spigelman told the National Press Club on Wednesday.

Selling off the ABC would make the broadcaster's services "unrecognisable," he added. "To use the word 'privatise' is an Orwellian corruption of language."

Many within the senior ranks of the ABC are worried that the Abbott government will make severe cuts to the broadcaster's budget.

Others within the organisation have taken note of comments made recently by the Prime Minister and Communications Minister  Malcolm Turnbull that criticised decisions made within the public broadcaster.

Both have publicly rebuked ABC boss Mark Scott for showing "poor judgment" by collaborating with The Guardian Australia to publish leaked details of Australian spies monitoring the phones of the Indonesian President and his wife.

ABC management's concerns are understood to have escalated amid a concerted campaign within the Coalition, led by South Australian Senator Cory Bernardi, to cut the ABC's funding and stop the broadcaster publishing news for free on the internet.

News Limited commentators and ministers in the Abbott government have increasingly been calling for the ABC to stop producing online content.

But Mr Spigelman said if that happened the public broadcaster would suffer.

“Getting out of online content would marginalise the ABC [because] that’s where everyone’s heading,” he said.

“In the long run we would decrease in relevance, [but] maybe that’s part of the objective, I’m not sure.”

He said the ABC had always impacted on the commercial interests of other media.

“In 1933 I think it was when the ABC first announced that it was intending to provide a news service, a campaign was launched to cut the funding of the ABC.

''That campaign was run by the then-CEO of the Herald and Weekly Times, Sir Keith Murdoch.

“Some things change very little over the generations.”

Mr Spigelman said the ABC was right to be publishing online news, even if it meant competing with commercial outlets such as News Corp and Fairfax Media.

"Some regard this form of competition by a public broadcaster to be 'unfair'," Mr Spigelman said. "However, that is the commercial effect of what the ABC has always done.

"There is nothing fundamentally new here. Nor are the complaints. Nor is the attempt to exercise political influence to restrict us."