Terpene synthase that catalyzes the conversion of (2E,6E)-farnesyl diphosphate (FPP) into sesquiterpenes which are important for fungi-environment interactions (PubMed:31239482). Produces a mixture consisting of 8 sesquiterpenes including corvol ethers A and B, as well as traces of epizonarene, gamma-cadinene, delta-cadinene, alpha-cadinene, alpha-cadinol, and an unidentified sesquiterpene (PubMed:31239482). The major product is corvol ether B (PubMed:31239482). (2E,6E)-farnesyl diphosphate + H2O = (+)-corvol ether B + diphosphate (2E,6E)-farnesyl diphosphate + H2O = (+)-corvol ether A + diphosphate Binds 3 Mg(2+) ions per subunit. The Asp-Asp-Xaa-Xaa-Xaa-Asp (DDXXXD) motif is important for the catalytic activity, presumably through binding to Mg(2+). Belongs to the terpene synthase family.