Recently added a sub to my car with an older amp that did not have a low pass filter. This solved the situation beautifully. Now my subs are no longer trying to cover the mids as well.
Add to that the remote volume control and now I can easily dial the bass back when I have those who cant handle it in the care or let it fly when I am on my own.
*** Oct 2013
This unit continues to be in service and is doing the job nicely. I am raising it to 5 stars.