@45Hz the port will be at its peak...it becomes extremely hard for the human ear to detect flats below 35Hz...at which point i dont care about that low anyway....and when i speak if 130dB i am not talking about the supersensitive dB drag mics. mounted on the bottom left corner of the wind sheild...i am speaking of 130dB in the center of the cab...and yes that is extremely hard to reach...i may or may not tune lower...but at hte moment i am going to tune to 40Hz most likely...