Subwoofer Frequency Response question


I just started testing my frequency response with a Radio Shack SPL meter (digital). My subwoofer is a Paradigm PW-1100 (10 in) with Green Mountain Europa speakers. The room is small, 12 X 14 X 9. The frequency response is generally very good with bass response down to 25 Hz. My issue is I have a dropout of nearly 20 db starting at 45 hz through about 70 hz. I have not been able to change it by moving the sub or changing the settings (phase and crossover point). I also have the sub on an elevated platform of 1 1/4 inch MDF with spikes between sub and platform.

I am wondering if adding internal bracing and additional acoustic dampening material to the sub woofer would change the response characteristics in a positive way.

Any ideas would be appreciated.
drewh1

Showing 1 response by eldartford

What you described, a deep notch at the crossover frequency, is the classic symptom of drivers out of phase. In fact this is the best way to find out what the crossover frequency is. Invert one driver, and look for the notch.