33% Off Cherry Audio Mercury-4 Introductory Sale – 33% Off The Mercury-4 synth captures the uniquely aggressive analogue tone quality of the legendary Jupiter-4. Buy now for only £29.95 / $39. Expired October 31, 2021 Buy Now All Sales Cherry Audio Mercury-4 Introductory Sale – 33% Off The Mercury-4 synth captures the uniquely aggressive analogue tone quality of the legendary Jupiter-4. Buy now for only £29.95 / $39.