(Andrea Shea, WBUR) The Isabella Stewart Gardner Museum is kicking into high gear now that the January opening of its new $180 million expansion is on the horizon. A state-of-the art performance hall is a big part of the upgrade.

This week — after five years of planning — the museum’s cube-shaped concert space is undergoing some pretty serious acoustical testing. On Wednesday morning I dropped in to see how it’s sounding.

When I arrived I expected seasoned acoustician Yasu Toyota to be plugged into all sorts of high-end, high-tech testing devices. But when he first assesses the sound of any space he actually goes no-tech, relying on some the most basic of human instruments: his hands.

“Like this,” Toyota said as he illustrated the age-old art of clapping. “So this is a kind of tool,” he explained, saying he also snaps and sometimes even pops a blown up paper bag. “And so if we could have some actual music we don’t need this.”