Of course, static disc images and the like do not require online hot backups as the data does not change except when adding to the library. So RAID is not necessary if an alternative reliable backup strategy is used. As well as the savings on not having to have expensive RAID kit, you get energy savings by not concurrently having to keep raid discs powered and the safety of having backups kept offline out of harms way of accidental or malicious harm.

Meridian owner since 1992
Prime & PSU, Focal Elear headphones, Roon (ROCK 8Gi5 NUC), Explorer 1 & 2, F80. 200/203, various Sonos (via Roon).