they're louder than most hubs....but a mate of mine has a pro 2 and whenever i ride with him the pro 2 drowns it out...still a loud enough hub though is the disc jockey
Nuke proof genrators are louder than normal Pro2's, but if you were to buy a Pro2 trials ss hub thts 48t to the ratchet so they click crazily whereas a normal pro2 is only 24t to the the ratchet.
A sunringle disc jockey is also 24t to the ratchet so really a disc joskey and pro2 make the same amount of noise, then theres the Nukeproof generator which is 30t to the ratchet with leaf springs so its louder and has a nicer sound to it.
Its not all about how clicky the hub is thought generally the louder the hub the more friction there is, if u want a fast rolling AND loud hub you gotta pay top but the Nukeproof Generator was your best bet but for an extra 50quid you could get the pro2 but at 50GBP more i don't see where my money is going apart from the brand name, as the Nukeproof is only 20grams heavier, is clickier just as smooth and also apparently out selling the pro2.
However the thread is so old you probably have had your PRO2 for like a month
actualy the hope pro 2 is MILES louder than the sunringle disc jockey because i have a pro 2 and my mate has a sunringle and my pro 2 absolutely drowns out the sunringle disc jockey!