Here are my intial measurements taken in my room using the HT shack Room EQ Wizard program (REW). I used a Behringer ECM 8000 measurement mic and a Behginer XENXY 502 mixer as a mic preamp. The following measurements are easy to perform, and the equipment is not costly. If you are serious about getting the best bass in your room, it's the smart thing to do.
The sub I'm measuring is the Rythmik 12" servo sealed sub which I have in a 70L box. I have two of them but measured just one. The idea behind these measurements is to determine the best locations in order the get the smoothest possible in room response.
First, nearfield measurements performed with the mic as close as possible to the cone. This removes the influence of the room.