Hi. Im doing some educational mixes from mt camridge and I was having problem with a kick in a metal drum mix. The kick has this weird ringing (like pre post ringing). When drummer goes in doing 16th twin kick its like overbearing and there is no definition. I applied high pass filters with different slopes added compression It just enhanced the same problem. Im reading about linear phase eqs and fir stuff and Reaper has Reafir and decided to use it. I did the same cuts as I did on eq and FFT is 4096 (I dont even know what it is I guess the length of the fir code?) and It cleaned up all the issues Im having. The kick is drier fast going in and out has more definition. I was expecting more pre-post ringing and added delay as they relate with fir eqs but It didnt happen (because Its playback?). Im also a bass player and and use tdr nova for live playing with my band. I tried to use Reafir but there was too Much delay which is impossible to record or play live and low fft sounded horrible. Can someone explain what's happening here? Thanks a lot.