Finding new ticket-buyers in Analytics

Hi all, 

I'm on a mission to track the number of new audiences coming in to our venue, per event. 

We have a T-Stats workspace which calculates the number of new ticket buyers and the quantity of tickets they purchased for a given event, but I've been told that it's not 100% reliable. 

In the transition to Analytics, has anyone built a similar model that they might be willing to share? 

Thanks!