I thinking of buying a sena smh5 and am just want to use it for music through garmin 660 so I don't need the mike , will the speakers be loud enough!! I like the idea of the Bluetooth I usually use ear buds with speakers opinion s please
) then, yes, the SMH5 does chuck out enough volume for your tunes. It's not hi-fi quality by any means and a waste of time if classical or subtle musical tones are your thing but fine for most of that new-fangled 'pop' or 'rock' stuff dontcha know! 
Sena do upgraded speakers for the SMH5 (using SMH10 SPEAKERS), we've sold a couple like this. The upgrade is another £23.99. We are Sena dealers.
Regards, [email protected]