The first pop act to perform at the Las Vegas Sphere, the Backstreet Boys’ took up a summer residency at the fully immersive venue to mark the 25th anniversary of the release of their Millennium album. Relaying the band’s performance through the Sphere’s 360° sound system, involved the use of an SSL Live console and five Digital Audio Denmark Core 256 interfaces for playback, to host plug-ins and for and recording.
‘This is a complicated set-up and a complicated show at one of the most sophisticated venues in the world,’ says FOH engineer James McCullagh, who has been with the band since 2013. ‘I’m using two Core 256s primarily to run plug-ins and to record. I needed a really small box with high-quality, high channel-count audio that could handle multiple different formats with the lowest possible latency.’
His Core 256 units each offer 848 channels of I/O, supports Thunderbolt, Dante, Madi, Adat TosLink and DADlink, and runs at sample rates of up to 384kHz with a latency of just seven audio samples.
Playback engineer Tim Rose, meanwhile, has a triple-redundant system of three Core 256 units configured for playback – the five Boys are singing without musicians’ accompaniment on these dates – involving around 400 tracks in Ableton bused down to 105 audio outputs.
The playback set-up is hosted on several maxed-out Apple Mac mini M4 Pro computers. ‘They keep reminding me in my camp that I’m the heartbeat of the show,’ says Rose, who was a full-time musician for nearly15 years before becoming a guitar tech then a keyboard tech. ‘Playback always appealed to me. A lot of people just don’t want to do it because it’s a high-pressure seat, but I’ve been enjoying the challenge.’
Elaborating on his system at the SSL Live console at FOH, McCullagh explains: ‘I’m using one of my DAD Core 256s to multitrack the show – that’s 160 channels that come in over Dante and then go to Reaper for recording. I wanted to use a lot of reverbs and I’ve got 16 CPU-intensive Bricasti emulations running. Those are on the second Core 256 that basically does all the heavy lifting. I’m running those on a Mac mini M4 Pro with Gig Performer software, and it works very well.’
Rose and McCullagh are among the first to use DAD’s new Control Pack upgrade, which supports channel-based redundancy for playback systems and live processing with manual or logic-based switching and show control. ‘I use the Control Pack AE 6 tone generation,’ reports Rose, to notify him if there is a failure. He is also taking a tone out of DADman, ‘The AE 6 is just a warning light but the tone generator within DADman will automatically failover the 128-channel Dante bucket,’ the term DAD uses to describe a set of routed I/O sources and destinations, up to a total of 256 per bucket.
‘The playback system is redundant, and obviously that’s where the Core 256 excels,’ adds McCullagh, who encouraged Rose to adopt the DAD components. ‘We chose it because it can failover using the Control Pack, the channel count, and because it has Madi and Dante. But what’s key about the product is that the quality is so damn good.’
McCullagh has used compression and EQ to help recreate the, big sound of the 1990s when mixing the Backstreet Boys live in stereo for years. But for the band’s Into the Millennium residency at the Sphere, he had to rethink his approach, since the venue’s 167,000 loudspeaker drivers, amplifiers and processing channels, configured as dozens of speaker clusters throughout the domed venue and behind the stage, presented new, immersive possibilities.
For the Sphere residency, Backstreet Boys are using a pre-recorded band produced by McCullagh and Keith Harris, the musical director and drummer: ‘We wanted it to sound like a real band; we didn’t want it EQ, compressed or edited,’ McCullagh says. ‘We were very cognisant of the multiple speaker arrays in the Sphere, and the fact that all the speaker arrays are basically distributing audio to all parts equally yet at the same time. You can’t put the same sound source in multiple speakers, because it will phase, so if we want a big sound, we need a big channel count.’
That approach meant that, for example, a single guitar channel from a musician on stage would be separated into, say, separate clean, dirty and lead guitar tracks on the pre-records. ‘The concept of how we broke it up was as if there was a real band playing,’ McCullagh elaborates. Every drum mic – kick in, kick out, snare top, snare bottom, and so on – is on a separate track, and the electronic drum kit and Roland SPD sample pad lines are also broken out. ‘So we can have percussion going to different parts of the Sphere.
‘It turned out that it wasn’t as easy to pan things because of the great distance and the timing offset. So, 80 or 90 per cent of the mix is in the center, then I ended up using reverbs. And that brings me to why I needed another DAD Core 256.’
Previously, McCullagh notes, he would have used onboard reverbs and maybe three hardware Bricasti reverbs. But on this show, he says, he wanted to be able to use as many plug-ins as he wished, without worrying about channel count, latency or audio quality. In all, he’s currently using 16 Seventh Heaven Bricasti emulation plug-in instances hosted on the Core 256. ‘What’s more,’ he points out, ‘being able to host so many emulations has saved the show production the potential cost of the equivalent hardware devices.