4600 concertgoers are consistently packing The AXIS at Planet Hollywood for Britney Spears’ popular “Piece of Me” residency. While they’re in their seats at one of the most famed theaters in Las Vegas, no one has to think about why they’re hearing precision, full-frequency sound – all they have to do is enjoy the show.

Criterion Acoustics (CA) was selected to provide the acoustical design as part of a full renovation for The AXIS at Planet Hollywood (aka The AXIS Theater) just prior to Spears’ residency, ensuring that there would be 21st Century production values for the platinum artist. Working closely with architectural firm Gensler and the venue’s ownership, CA took on the challenge of working with the existing theater geometry while elevating it to the world-class acoustical standards that Las Vegas theatergoers expect.

The project itself was complex, but the timeline made it even more daunting: CA had only three months from the point that they began drawing up plans, to the renovation’s completion. “We really fast-tracked the acoustical treatment’s design and production to get everything completed on time,” says Dave Kotch, President of Criterion Acoustics.

The constant evolution of large performance venues meant that the renovated AXIS Theater would have to meet a significantly higher standard than its previous incarnation. “Loudspeaker systems have gotten better,” Kotch observes. “Distortion is significantly reduced, so shows are getting louder. The objective is to have an essentially dead theater, with excellent low frequency control.

“The venue had multiple issues with the internal room acoustics prior to the redesign,” continues Kotch. “When The AXIS Theater was originally built, they didn’t have the Vegas-style performances of today in mind. The room has a huge dome, for example, which makes it hard to handle acoustically. To make matters even more complicated, the dome is a wooden structure – it was an architectural element that we couldn’t change or modify.”

Kotch and Sam Neff, Vice President of CA, devised a plan that would control the reverb time, and manage low-frequency buildup in the theater. The centerpiece was a massive broadband low-frequency absorber measuring 50 feet high by 400 feet wide. “It’s huge,” says Kotch. “There were limited places that we could place treatments, so making it work within the constraints of the space and budget were obstacles we had to overcome.”

CA’s analysis also revealed that the AXIS Theater’s dome was throwing unwelcome energy back onto the stage. “The artist would hear the reflections,” Kotch notes. “We placed treatments strategically around the perimeter to eliminate the issue.”

In addition, CA provided systems engineering and documentation support for 3G Systems, the live sound provider.

The result was an acoustical overhaul that helped transform the sound of the AXIS Theater — and Britney Spears’ “Piece of Me” show keeps going on, with two extensions in 2015.