OK turbos and blowers both work by spinning an Impeler and forcing air in to the intake plenum. Since blower and turbos do "work" by spinning a stuffing air into the intake some of this "work" is lost as heat. The intercooler is added on to these systems to cool the air that is being stuffed in to the intake plenum engines like cool air. They are usally water cooled too, they also work to keep the turbo of blower cool too so they will last longer.
In a nut shell they are like a radiator on a car but just for the boost system.Like radiators they make little noise.
Intakes don't make noise but hte engine does suck vaccum from the throttle and you can here vacum when the intake snorkal is removed.So techniacal the engine makes the noise not the intake.
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