Shure SE846-CL Sound Isolating Earphones with Quad High Definition MicroDrivers and True Subwoofer Quad Hi-Definition MicroDrivers: For extended high-end clarity and unparalleled low-end performance Patented Earphone Design with Groundbreaking Low-Pass Filter: Provides previously unattainable deep low-end performance of a True Subwoofer without sacrificing clarity or detail Customizable Frequency Response: Adjustable sound signatures available (including balanced, warm or bright) via changeable nozzle inserts and removable, metal nozzle NOTE: Refer the User Manual and the User Guide before use.Sensitivity - 114 dB SPL/mW. Frequency Range - 15 Hz20 kHz Convert Shure SE846 Earphones to wireless with the new Bluetooth-Enabled Cable (RMCE-BT1). Sold separately.