One of the best things about La Marzocco espresso machines is that they are built from scratch. In fact, they are handmade, and they are hand-tested. This is why the machines are worth the investment. It's also one of the reasons many people consider the brand's coffee machines to be superior to other brands' machines.

The AV (automatic volumetric) offers software-driven, highly accurate volumetric brewing with programmable doses. The EP (electronic paddle) versions allow you to introduce water at the pace and pressure you set and control by hand.

However, the most common espresso machine used in Starbucks stores is the Mastrena High-Performance Espresso Machine, which is made by the Swiss company Thermoplan AG. The Mastrena machine is designed specifically for high-volume environments like Starbucks, and it's known for its speed, consistency, and ease of use.

AV stands for Auto Volumetric. This means that the espresso shot is started by the barista, then your Linea PB AV espresso machine automatically pours a pre-programmed amount of water through the grouphead to reach the right amount of coffee that you need.