RAC seats 8000, which has gone down in recent years. Used to be closer to 9000 when it opened in 1977 (and I think it was around 8300 when I was at RU in the late 90s), but they reconfigured some things over time (some for more premium seating that took up more room, and some for fire code issues I think). There's talk every year about what could be done to pack in another couple thousand, but it's only very recently that we've been consistently selling out to make such an expansion worthwhile.
Its architecture is fairly brutal, but it really gets loud at court level (some fans unofficially clocked the peak at a recent game at 113 decibels - which is like a chainsaw 3 feet away). The pitch of the stands is very steep, so the fans are almost right on top of the court - it doesn't slope gradually away from the court like most venues, and apparently building code has changed such that you can't build stands that steep anymore. My kids don't like climbing to the top - it's definitely not for people who don't like heights.
There's really nowhere for the sound to go, as the trapezoid shaped metal roof just reflects everything back onto the court.
