The new Sony cool gadgets headphones not only have no loss of sound but also a design with perfect endings. The MDR-XB40EX and MDR-XB20EX not have this design’s sake, but they are done this way because this is thanks to reduce the loss of sound. The MDR-XB40EX has a frequency from 4 to 24,000 hertz, a 105db/mW sensitivity and an impedance of 16 ohms.

Moreover, the MDR-XB20EX has a frequency of 5 to 23,000 hertz, a 103dB/mW sensitivity and an impedance of 6 ohms. You can buy them since November and leave for 24 to 40 euros.
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