Someone did posted above saying earphone/headphone cut surrounding sound, it's correct, but low level speaker in helmet is safer.
RIders do have large field of vison, we have less blind spot compared to cars.
So a rule regarding playing music in Automobile should be stricter for cars than Motorcycle riders.
Also using speakers with low level volume in helmets helps in long highway rides, in city should be avoided since there are so many variables to look, especially olympic crowds who likes to beat motorcycle in crossing.



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