There was an amusing blog post on the Toronto Star site on the ACC crowds. The premise was that if Maple Leaf fans were more vocal, like those in Philadelphia, Chicago, Detroit and Washington, they would lift the team up and act as a “sixth skater”. The blogger goes on to suggest some interesting (though hardly realistic) ideas like moving the real fans in the purples to the lower bowl or recruiting the loudest and craziest Leaf fans in the city and give them season tickets.
I was at the game on Monday and there were long stretches of absolute silence. Those stretches coincided with long stretches of boring hockey - pucks constantly turning over in the neutral zone, dump ins, and pointless cycling along the boards. However, when the action picked up, like when the home side actually skated hard, the crowded got louder. It may be a chicken or egg analogy but I think the team gets the crowd into the game by creating scoring chances. The visiting teams know that the best way to neutralize the crowd is to get one or two early goals.
You can’t artificially generate noise. Like when the team flashes on the big video screen to make noise. There are a few thousand lemmings in the crowd that will scream for 30 seconds but then the place dies right down again. I've been in the ACC when the place is electric. It's actually not very difficult to get Toronto fans excited. Just play some decent hockey. However, most nights the t-shirt toss during a break gets more of a buzz than the hockey team.