With four high-definition drivers, a groundbreaking low-pass filter for true subwoofer performance, and a customizable frequency response, the SE846 Earphones are engineered for a perfectly tailored l more→istening experience. Four Hi-Def Drivers Four high-definition drivers in each ear for extended high-end clarity and a groundbreakingly low-pass filter for true subwoofer performance in a convenient and portable package. Sensitivity: 114 dB SPL/mW. Frequency Range: 15 Hz –20 kHz. Speaker Type: Quad High-Definition. Impedance: 9 Ω. Sound Isolation Comfortable sound isolating sleeves block up to 37 dB of ambient noise. Sound isolation technology prevents outside noise from interfering