7.2.1 Funding and Technical Knowledge  It is quite possible to build a low cost digital preservation system, but this cannot be achieved without at least a small level of technical knowledge and some recurrent resources, albeit at a low level, to make it sustainable. Regardless of how simple or robust a system is, it must be managed and maintained, and it will need to be replaced at some time or risk losing the content it manages.  “Digital preservation is as much an economic issue as a technical one. The requirements of ongoing sustainability demand at their base a source of reliable funding, necessary to ensure that the constant, albeit potentially low level, support for the sustainability of the digital content and its supporting repositories, technologies and systems can be maintained for as long as it is required. Such constant funding is not at all typical of the many communities that build these digital collections, many of which tend to be grant funded on an episodic basis. There is therefore a need to develop costing models for sustainability of digital materials according to the specific requirements of the various classes of content, access and sustainability.” (Bradley 2004).  It is inevitable and unavoidable that the system and its hardware and software components will require maintenance and management which will demand both technical knowledge and dedicated funds. Any proposal to build and manage an archive of digital audio objects should have a strategy which includes plans for the funding of ongoing maintenance and replacement, and a listing of the risks associated with the loss of technical expertise and how that will be addressed.