I want to clarify that I have the MK2 version of the MDR-1BT not the EC7 version, available for now in Asia. On paper, the two versions are similar set apart the MK2 has increasingly apt-X Bluetooth for wireless transmission of better quality. In practice, the autonomy of continuous music 30h and 200h standby sets the tone. we can now let the paired PC 24H / 24 without running every 2 days behind a charger. Musically, after a short break-in period of about fifteen minutes, the quality is revealed. For me the sound is perfect, very present bass without obscuring the midrange and treble. apt-X codec (for mk2) is a must that allows me to have a bluetooth transmission in HD with low-synchronization image / sound during a video viewing. It is finally possible to enjoy movies, or even sounds from your tv / games (if you have a suitable transmitter: the saturn for TV, btd 500 for pc for the headphone remote control). Regarding the codec sbc / aac for EC7 version quality is still satisfactory, but a little worse than if you wire it. In summary I am amazed by the sound quality of this headset, deserves to be much more popular. PS: If you choose me as for the mk2 version do not forget to change the setting in apt-x because factory is set to SBC ....