The home was designed in 1919 by New Zealand architect Roy Binney for prominent businesswoman Amy Hellaby, of the meat and smallgoods company.
It was part of a divorce dispute between former rich-lister John Sanders and his wife, Yvonne, before the Herberts bought it in January last year.
Property developer Simon Herbert said he and his clothes-designer wife loved their new home: "We are delighted - it's a beautiful property."
The cocktail party would include a guest appearance by Australian DJ Ruby Rose, who makes appearances endorsing LG Electronics. Ansin would not be drawn on the product to be launched but invitations described it as a "revolution in home entertainment".