B3 lavalier should always be used with a protective cap in place to keep sweat, makeup and other foreign material out of the microphone. The three omni caps each have a different high frequency response characteristic that controls the amount of “crispness” or “sibilance” . The B3 ships with the +0 dB (flat) protective cap fitted to the mic. Switch to the +4 dB or +8 dB cap to boost the perceived amount of “presence” in your sound, while leaving the lower frequencies unchanged.