Bluetooth is one kind of the open type standard that the wireless data and implication transfer. Bluetooth usage 2.4 GHz low frequency, which is not same the cellular phone that high frequency used by it, the what be come into being electromagnetic wave can not pass through the human body, can not have effect to the healthy of human body. At present popular Bluetooth equipment gives first place to wireless short distance connection, is to arrive at ten-meter range ten centimeters .in general, if needing to increase power for peculiar, adding the special-purpose amplifier, whose effective range can reach the distance is one hundred meter.
Bluetooth agreement could include cellular phones, PDAs, notebook computers and related peripherals numerous exchange of information between devices. And in a variety of Blue tooth, which the most colorfully when a few can allow users to a large extent and total liberation in the hands of Bluetooth headset. Although this is some small thing, it can indeed make our lives more convenient and satisfactory.
At present popular Bluetooth of way earphone is headset main ear bud and ear-link the two, if according to wearing the Bluetooth of classify. Related to Bluetooth headsets technical parameters: Headphones technical parameters are very important
We need the Bluetooth headset not only listened to phone, but also needed it have more time to appreciate music, Therefore, we should pay attention to when buying a headset which impedance, sensitivity, frequency response and distortion, and several other very important technical parameters.
Impedance: the exchanges impedance of the earphone shorter form. Different impedance headphones for different occasions, the low-impedance headphones are easy to drive.In general, Desktop or amplifier, VCD, DVD, and television are using high-impedance headphones, but such as a portable MD, MP3 player, cell phone can use be general low-impedance.
Sensitivity: That is sensitive grading, high sensitivity means that the sound level, reached a certain sound level for small power, and that there are similarities impedance.
Frequency response: Sensitivity headphones come in different frequencies have different values for frequency response. The scope of the hearing is 20 Hz-20000Hz, outside the range of the voice; the overwhelming majority of the people cannot be heard. Frequency will depend on the sensitivity of relations with that curve out that is known as frequency response curve. In general, headset is not the frequency response flatness of±10dB, professional headphones and certain high-grade headset is not the frequency response flatness of ± 3dB, so that the frequency response is not the higher the better.
Distortion: Benefited from its low-power headphones, headphone speakers harmonic distortion generally much smaller than the maximum under power when its total harmonic distortion THD less than or equal to 1%, the human ear is basically not identify.