Although her work station is located in a seating area, there are no spotlights on Ruiz, no obligation to perform for the crowd, which frees her up to keep a watchful eye on the game. Until it's snack 'n' pee time, the other spectators are focused on the ice, unaware that the greatest concentration of power in America West Arena isn't the 10 guys with unpronounceable names bashing each other against Plexiglas, it's this quiet but steadfast woman with the headset, digital recorder and 88 keys.
Fans arriving for the Penguins game are being mood regulated by Ruiz from the moment they amble through the turnstiles 'til the clock is stopped. And it's a task she performs with all the anonymity of an air-traffic controller.
There are occupational hazards. After two parched years, beer has been splashed on the mixing board in recent weeks.
"A fight broke out," Ruiz says. "Somebody threw a beer at somebody and it all came up here."
Sound engineer Derrick Wilson had to do some quick mopping up. "Nothing got into the faders, fortunately," he says.
But even if another suds downpour were to short-circuit the board, another mixing board awaits, secure under a nearby tarp.
"We're redundant about everything," Wilson adds. "If the board dies, I can run it off this. If our speakers blow up, I got those backups," he says, gesturing to the ceiling.
But what if Ruiz suddenly gets food poisoning? Clearly someone has already considered that emergency scenario, which is why Ruiz was recording some of her keyboard prompts earlier in the day. It's a precaution no one believes or hopes they'll ever have to exercise.
"She's always here," Wilson says, smiling. "We don't want anything to happen to her."
Perhaps a stomach pump is also at the ready.
Iralson admits that Ruiz and her gear would be a lot more secure under glass, but reckons "this still works out the best. Because when you're in an enclosed room . . . and hearing everything through a speaker, you really don't feel the game, don't know what's going on. Here she's in the middle of everything. She can make suggestions and know where we should go."
Ruiz's view of the ice can be obscured if all the seats in front of her are filled to capacity and people stand up (although this is Phoenix, a city whose motto could be: "We take our entertainment sitting down"). To fill the blind spots, she is kept well informed by Iralson and others who don headsets. Constant chatter occupies her left ear throughout the night while her right must monitor what she plays on a tiny speaker set off to the side.
"Some nights it's kind of tough when I'm not feeling so secure about the playing. One little mistake and everybody hears it," she says, grimacing. "It's kind of stressful. The first couple of games were especially rough because there's a significant delay in what I play and what goes out there. I wasn't prepared for that. The guy that trained me said, 'Oh that's nothing.'"
Ruiz was fortunate enough to know the previous "music director and keyboard operator" before landing his vacated slot (he now plays for the L.A. Kings).
"It takes a while to fall into the rhythm of this job. It's a learned skill."
And her attitude toward hockey?
"I'm Canadian and I'm kind of born with it. But I've lived here for a long time and for a long time we didn't have any hockey here. I was a big Kings fan for a long time. That's about all we could get on TV.
"I thought I knew a lot about hockey until I started working here. I was just used to sitting back as a spectator waiting 'til the ref tells you what the penalty is. On this end, we've got to know what it is before they tell everybody. You can't doze off at all. You have to be ready to jump on a situation. All of the sudden there's a penalty coming up and we drop everything we had ready and play something like 'Breakin' the Law.'"
While some stadiums use prerecorded keyboard prompts such as "Charge!," which require the minimum amount of piano technique, the human touch provides crucial timing.
"It's NHL policy that we have to cut out of whatever we're doing when the puck drops," says Ruiz. "If I wanna get in a 'Charge!' or something, and I can see they're gonna drop it quick, then I can speed up so we get it all in. If it's a recording, we can't control the speed of it."