The Backstreet Boys have become the first pop act to headline Las Vegas’ Sphere, launching a summer-long residency marking the 25th anniversary of their Millennium album.

To meet the venue’s unique 360-degree audio demands, front-of-house mixer James McCullagh and playback engineer Tim Rose relied on five Thunder | Core-powered Digital Audio Denmark (DAD) Core 256 interfaces.

The compact yet powerful Core 256 delivers 848 I/O, supports Thunderbolt, Dante, MADI, ADAT TosLink and DADlink, and runs at sample rates up to 384 kHz with latency as low as seven samples. “I needed a small box with high-quality, high-channel-count audio that could handle multiple formats with the lowest possible latency,” said McCullagh, who has mixed the Backstreet Boys since 2013. He employs two Core 256 units for recording and plug-in hosting, including 16 CPU-heavy Bricasti emulations running on a Mac mini M4 Pro.

Meanwhile, Rose manages a triple-redundant playback system of three Core 256s, driving about 400 Ableton tracks bused to 105 audio outputs. With no live band onstage, Rose’s setup — hosted on maxed-out Mac mini M4 Pros — provides the backbone of the show. “They keep reminding me that I’m the heartbeat of the performance,” he said.

Both engineers are early adopters of DAD’s new Control | Pack upgrade, which enables channel-based redundancy, logic-based switching, and show control. Rose uses its AE 6 tone generator to monitor system health, while McCullagh emphasizes the Core 256’s ability to failover seamlessly: “The quality is so damn good.”

Mixing for the Sphere required McCullagh to rethink his approach. With 167,000 speaker drivers across the domed venue, he and music director Keith Harris created detailed pre-records mimicking a full band, with every guitar layer and drum mic separated into discrete tracks. “If we want a big sound, we need a big channel count,” McCullagh explained.

Despite the complexity, much of the mix remains centred, with reverbs used to enhance immersion. Hosting multiple plug-ins on the Core 256 not only delivered the required processing power but also saved the production the cost of dozens of hardware units.

For more on the DAD Core 256, visit www.digitalaudio.dk