Hello, I am new to this list. Please excuse my post if it is not on topic. I am trying to do the following: create a test disk that has tracks 30 sec in length each track will be a specific hz frequency 25 hz 30 hz 35 hz 40 hz and so on.... Once I figure out what the lowest frequency my car system can reproduce cleanly, I would like to try and filter out everything below that frequency. So lets say my sub hadles 30 hz and above. I would like to "process" my music to remove everything below 30 hz. I was playing with rezound and the TAP plug-ins but I was not able to get a clean break at a given frequency. any help is apprecitaed. thank you for your time and have a good day. -- View this message in context: http://www.nabble.com/rezound%2C-test-disk-and-subsonic-filter-t1308910.html#a3487300 Sent from the linux-audio-user forum at Nabble.com.