- Wired monitor headphones HAVIT HV-H2178d offers high quality sound. The minimum playback frequency is 20 Hz and themaximum playback frequency is 20,000 Hz along sensitivity of 110 dB. The device offers a popular high-frequency mini jack connector with a 3.5 mm straight configuration. Equipped with a flat cable, which doesn’t get tangled. The cable length is 1.2 meters which is easier to use. Such a constructive solution allows user to listen to music from a smartphone or tablet and answer the calls. Soft ear cushions from kozhzama, make listening more comfortable.