Contour Enthusiasts Group Archives Forums Modifications Audio resonant freq. of 1995 contour

I've been competeing in DB drag racing for sometime (SPL events). and I just got a 19995 contour not that long ago. I need help to finding the resonant freq of the inside cabin of the car. I measure the distance from the sub facing to the placement of the SPL meter, and mathematically came up with 43HZ. but I'm 100% if that going to be my resonant freq of the cabin.

I would just put in a test tone CD with individual frequency steps and measure the loudest response.

You should find cabin gain increases greatly at 43 Hz but the peak is around 63 Hz.

thats a 20hz difference! maybe I'll start with a 50hz tune and work up from there. man I need a personal meter.