Hello and Welcome to the forum!
But if you want to make some speakers in your helmet, Contact the police first and ask if it's legal.
I know a mate who has done that before and when he got a speeding ticket, the officers saw there were speakers.
He got a ticket for that aswell because it may inflect the safety and durability of the helmet.. LOL
Anyway, If i were you i just bought the original HTC headset wich is wired, and plug them in my ears.
Put on your helmet and you can call and such.
But maybe other people will have some other thoughts.
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