Listen to the ambient albums created by Ildjarn. They aren't really the same thing, but they do use only synths. Landscapes was released as Ildjarn, and Hardangervidda and Hardangervidda Part 2 were released under the Ildjarn-Nidhogg name. Even if you dislike his black metal music, these sound literally nothing like it.
If you like Ildjarn's music, you should probably also check out Biosphere because he was probably the biggest influence on these albums.