The ABC is dismantling its historic sound and reference libraries across the country and making 10 specialist librarians redundant to free up floor space and save on wages.

Radio National, Classic FM, JJJ and all the other ABC programs rely on the Sydney, Adelaide, Melbourne, Perth and Hobart libraries, which are packed full of CDs and vinyl as well as books and journals after 85 years of collecting.

The librarians know the collection intimately and suggest music for documentaries and other programs.

The libraries will be “culled and packed” to reduce duplication and to “align with production requirements”, according to the staff announcement.

A single “consolidated” library will survive in Melbourne with a skeleton staff who will digitise a fraction of the collection. A small classical music collection will remain in Sydney for Classic FM.

Last year all but one of Radio National’s music programs were decommissioned and eight specialist broadcasters were made redundant, turning RN into a talk-only station.

Staff fear the downgrading of music will affect the quality of Radio National and reflect the watering down of specialist content across the ABC in recent years.

Library sources say they believe only between 5% and10 % of the collection will be digitised into the Broadcast Music Bank and only 700 of the more than 100,000 CDs have been digitised so far. They fear the reduction in choice and expertise will “homogenise” the music heard on the national broadcaster.

Staff were told that the 373,000 vinyl records “will be dealt with following the transfer of CDs”. No changes have been announced for the ABC’s archives of film and tape.

The future of a specialist world music collection in Perth looks bleak. “Given the size of the current world music collection in Perth, and that its use is now minimal, this part of the collection will be subject to further analysis, along with the vinyl holdings, to determine the future of these CDs,” management said.

The memo said: “Sydney will be the priority to free up floor space followed by the other states and territories with the CD work completed by May 2018.”

The musician and former ABC broadcaster Lucky Oceans, whose 25-year-old show The Daily Planet was axed last year, said he was shocked by the speed at which the libraries were being dismantled.

“The theory behind it is that people aren’t using hard copies and that it’s all digitised,” Oceans told Guardian Australia. “But you know it’s those same people who were saying that vinyl is dead. It’s short-sighted in that way. You walk into a library and you look through the racks and you find a programming idea. And I don’t think it’s good enough that it will only be in Melbourne.

“The Perth library was very lucky because when they sold their vinyl collection they found a buyer but I would say that that is less likely for the CDs, which aren’t in favour at the moment.”

Oceans said while digitisation was inevitable, the ABC should retain the librarians “who are such an integral part of the ABC going back when the ABC produced so much more music”.

One former sound librarian said the extensive collections in Adelaide and Sydney would all but disappear, along with all the skill and knowledge of the library staff.

“This is yet another ‘death by a thousand cuts’ inflicted on all music resources in the ABC,” he said.

Staff were told the changes were to “better align our operations with the ABC’s strategic aims”.

“With digital technology now available, we can move our sound and reference libraries from operations based on multiple physical collections of information and music, to more efficient digital services which can be accessed by content makers anytime, anywhere,” a staff email said.

A spokeswoman for the ABC told Guardian Australia the number of CDs to be digitised would be determined by “the needs of the content makers”.

“Under this proposal the sound library collection would be centralised in Melbourne and librarians there would continue to provide expert knowledge to assist content makers around the country,” she said. “With the closure of the other physical libraries, the roles there would not be required.

“The new digital Broadcast Music Bank service has only been operating since late 2017 and CDs have been digitised into it as requested by content makers.

“The reference library services are currently based in Sydney and Melbourne, and book loans have reduced dramatically. We are not planning to digitise the books. Under the proposed changes we would move to a digital delivery model using e-resources, such as journals, e-books and databases.”

The section secretary of the Community and Public Sector Union, Sinddy Ealy, said the plan was irresponsible.

“The ABCs decision to sack specialist staff supporting journalists and program makers before the ABC has even bedded down the new content restructure is irresponsible – not only will it undermine the editorial quality of ABC content audiences rely on, but it is likely cost the ABC and taxpayers more money than it saves.”