Today, the place is strikingly silent. The only people present are a scattering of workers doing maintenance, and John Sharkey, the soon-to-depart chief executive of the parent company, SECC Ltd, who is talking about the success of the £125 million venue.
"Without a doubt," he says, glancing around him, "it has been worth it. Absolutely.
"The intention, back at the beginning, was to create a world-class venue. This was at a time when we didn't have a world-class venue [the SECC] and we were wedging concert business into its halls. We wanted to create something that was world-class, but also to give the fans a much better experience, to be able to offer them a better product whether it was in food or merchandising."
There were other aims, too: to allow the company to manage its costs and operations better, and to free up the SECC for more conferences and exhibitions.
And a key aim, one that would obviously underpin the rest, was this: to attract artists that the SECC had previously been unable to get, either because of tour availability or, in Mr Sharkey's words, "because there were some gigs that artists wouldn't come to play in Hall 4 for".
And that is what has happened. Beyonce, without question one of the biggest stars in the world, is doing two nights at the Hydro next month. It's one of only four venues on her UK tour; tickets sold out almost as quickly as you could say her name.
The BBC sitcom Still Game has sold some £10m worth of tickets for its 21-performance live stage show beginning next September. Justin Timberlake will be here in April; Miley Cyrus, Katy Perry, Barry Manilow and The Eagles in May, Robbie Williams in June. "The content stream is just unbelievable," says Mr Sharkey.
In addition to these shows, the venue will also host wrestling, three nights of the BBC petrolheads' show, Top Gear, Strictly Come Dancing, and a Celtic Connections Burns concert, to say nothing of Premier League darts, comedy (John Bishop, Miranda Hart, Jack Whitehall, Lee Evans, Russell Brand), Disney on Ice, Commonwealth Games events and the MTV Europe Music awards.
The appeal of what Mr Sharkey terms the 'Albert Hall meets the Coliseum' environment has plainly achieved results.
"Without a doubt, there's a Hydro factor in an awful lot of ticket sales," he says. "We've been meeting agents in London, who say the feedback from artists is that there is already a distinctive Glasgow atmosphere in the Hydro, as in the Barrowlands or King Tut's, but scaled upwards."
Commercial sponsorship has been another success: "Before the doors opened, we were targeting £300,000 a year: now, we're just under £3m a year.
"That allows us to take long-term decisions because we're not running around trying to cut corners. We can afford to invest in a really good customer experience."
How ambitious can the Hydro be? If, say, the reformed Monty Python team, who are playing 10 nights at London's O2 this summer, went on tour, could Glasgow feasibly attract them?
"If they tour, I fully expect we would get dates here from them," responds Mr Sharkey confidently. "The only artists we won't get are the kind who are doing big stadium tours, or those artists who're doing 20,000-capacity indoor venues on a strictly limited-date tour."
As for the future, thought is being given to getting the car-parks cleared more efficiently and to develop new content.
"I can see," Mr Sharkey says, "a festival being developed here, or something that runs across the whole campus [Hydro, SECC, Clyde Auditorium], as a vision we'd like to create.
"The festival needs to be something that attracts an audience into Glasgow. There are a million festivals out there so you'd need something that would fit with an unusual audience destination.
"Could it be that you do a dance-music festival, outwith the Ibiza scene, in the winter? Or might it be something more traditional? Whatever it was, we would need to ensure we stick with it for at least a few years so that it becomes established, and prospers."