It appears always after connecting carbon filter, maybe my filter is resonating, maybe it adds too much resistance. Maybe other people are not worried about this sound like i am and dont notice it. Im just tired this endless battle
. Its funny that i didnt had this problem when running 5-6 in 2x4 and now it creates problem with my 2x2 on lower setting. I heard that it whines a little when switching levels so i guess changing pressure drop in system can help. I hope just that my neighbours wont notice it through ceiling. I cant hear it through nearest wall. I have prima klima's filters pressure drop and bigger filters create less resistance in summary (less stepped curve). Im literally laughing at myself for how much i overthink it and how long this thread has become. Has anyone used two silencers in a line and notice big difference in airflow beetwen 1 vs 2 of them ?