a ? for u all

I have a 98 ex civic and i was gonna get a Evo til i got screwed up my ass... I sorta lookin at a hks hyper and i have heard it on a 98 ex, turbo'd ls, and a Si. THey seem pretty deep my question is are they quiet in the lowe rpms and get loud in the higher rpms?? If u could tell me ill be appreciated.. thanxs bye