In this you can separate bass sounds and treble sounds according to the users need. The Bass sounds are produced at the Sony gives the world of real sound experience yet another speaker which mimics the audiophile grade front-facing speakers. The extended bass reflex duct which it will penetrate directly into the ear canals. These speakers are positioned perfectly to give the greater sound experience. The features of the personal field speakers are:

Impedance: 16 ohms at 1 kHz
Mass: Approximately 7g (the cord/code excluding
Frequency Range: 35-25,000Hz
Sensitivity: 93dB/mW
Max input: 60mW
Power Source: 2 x AAA batteries
Playback time: Approximately 45 hours
Cord/code: 1m
Plug: Gold plated stereo mini- plug
Weight: 93g

Only confusion after you look all the features you will think whether it is a speaker or a headphone. The price of this personal field speaker is $499.
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