Retrosphere is an Spectrasonics Omnisphere Library created by Youngkio.
This library includes presets that are based on retrospective analog synthesis from the 80's, which makes it a perfect library to add to your Omnsiphere collection.
Update 2.0: This update also includes 5 bonus samples made with the Omnisphere library mentioned.
NOTE: Requires Omnisphere (2.5+) & Keyscape.