How do you choose the right speaker or subwoofer for your application? Well of course you have to know the size and power handling... but what do the rest of those numbers mean? These are the Thiele Small parameters and once you understand these speaker parameters you can pick the perfect subwoofer for YOU. Here's what Fs, Qts, Qms, Qes, Vas, SPL and the rest of the subwoofer specs mean!