vw beetle 90 to 120 amp alternator help please
 

Just got a 01 turbo diesel Beetleand I was driving down the highway and my alt died, the engine got real loud, so i pulled over at a shop and put a charge on my battery to get me home.. after i charged the battery the engine got quieter. now there was a 90amp bosh alt on it, i replaced it with a 120amp alt.. now the engine runs loud all the time, sounds the same it did when the battery was low. is it possible the alt swap did this and/or how can i quieten it back to how it was? THank You