Battery power supply for Destop PC (as audio server)

I am using a desktop PC as an audio server for a high-end audio system. It begins to be clear that one of the limitations is that ac sources are very grungy, and that power supplies are both physically noisy (fans, etc) and generate still more grunge that causes problem with very sensitive digital to audio converters and preamps.

I suppose the need to run desktops on dc direct from SLA batteries is not common, but surely there are other applications that needed to do this.

I have googled everything I can think of and have found any leads. What is there out there?

thanks, db