I haven't but I'd treat my sidewalls before wholesale radiation treatment with felt donuts. You might NOT want to affect the power response of your tweeter just yet.
If the tweeter high-pass is a crap capacitor than playing with better ones, or adding a small great bypass is usually a worthwhile experiment. You should hear differences.
Similarly, if you fingd small iron-core inductors in the woofer's low-pass, swapping them for large-gauge air core can definitely improve dynamics and lower distortion due to lack of early saturation. Have fun.
If the tweeter high-pass is a crap capacitor than playing with better ones, or adding a small great bypass is usually a worthwhile experiment. You should hear differences.
Similarly, if you fingd small iron-core inductors in the woofer's low-pass, swapping them for large-gauge air core can definitely improve dynamics and lower distortion due to lack of early saturation. Have fun.