Stage One BMW Speaker Upgrade for F25/F26 X3/X4 with Standard Hi-Fi 340 Even though our woofers are

Even though our woofers are designed to be extremely efficient to maximize the output of your factory amplifier

They are functioning as woofers (not dedicated subwoofers)

Stage 2 91 octane: 28%HP / 42%TQ

Welcome to the sales

Multiple expansion ports for larger BOV line

Stage One BMW Speaker Upgrade for F25/F26 X3/X4 with Standard Hi-Fi 340 Even though our woofers areGET UNBELIEVABLE, CRYSTAL CLEAR SOUND. JUST BY REPLACING YOUR BMW'S SPEAKERS We took your factory BMW speakers and re engineered our upgrade for one thing: clarity. So you can simply swap your original speakers for ours without changing anything else in your audio system, and the result is smooth, natural, yet unbelievably detailed reproduction of your favorite music. PLAY YOUR MUSIC LOUDER. AND ENJOY EVERY NOTE: We engineered the Stage One speakers