What is the output at 1K? What speakers are you using? What is the crossover frequency?
Room modes and/or phase cancellation between your two subs.Why are the lower frequencies so uneven?
Alan P - Thank you for pointing me in the right direction. I have just purchased the Paradigm Perfect Bass Kit which will work with my 2 Paradigm Millennia subs. It is supposed to smooth out the peaks and valleys and calibrate the subs to my room. It also has some great graphs to review before and after. I will send an update after I try it.Room modes and/or phase cancellation between your two subs.
If you could see your bass response, it would likely look something like this:
This is just an example of a measurement of my subs in my room, your peaks and troughs may be at much different frequencies and may differ in amplitude, it all depends on the room and on how well you integrated the two subwoofers.
In the modal range of frequencies (those below the Schroeder Frequency of a particular room), the sound waves do not behave the same as they do in the upper frequencies. This is a very deep subject, and trying to explain it all here would take too much time. I suggest you do some research on your own (you can start with the Guide to Subwoofer Calibration and Bass Preferences linked in my sig), then come back if you have more questions!