I have a hearing loss, and normally wear hearing aids. On the bike, I wear earplugs so as not to get any further hearing loss.
With the earplugs in, I have to turn up the volume on my Sena SMH-10 to max, and that's just barely enough.
Recently bought the
Etymotic Research MC5 Noise-Isolating In-Ear Earphones. They have 33db of sound isolation (as much as my earplugs), so now I am putting the sound directly into my ears, getting good noise isolation, and the Sena's volume can be dialed way down and still give me good volume.
And they set deeply into my ears and fit nicely under my helmet, without snagging it.
Only negative is that they have somewhat flimsy wires and I'm afraid I'll eventually pull them out. But so far, they work great.
BTW, I tried PlugFones awhile back - they were so bad (lousy sound and poor sound isolation), I trashed them.
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