Why are wireless headphones so rare?


Almost everyone I see using a portable music device is using headphones tethered to the device by a wire connection. I use them too, but the wire is a pain in the butt to say the least and constantly gets tangled. This must happen to others as well and there are wireless headphones out there that aren't outrageously expensive and get at least decent reviews soundwise (I just checked this out). I'm probably going this route but just wondering why the wireless 'phones seem so rare out there? Why do people keep putting up with the hassle of wires? Is it just a lack of knowledge about wireless headphones? Anybody have experience using these products? Thanks for thoughts.
soix
"Why do people keep putting up with the hassle of wires? Is it just a lack of knowledge about wireless headphones?"

That may be one reason. For example, I know little about them these days. Are there wireless headphones that test out as well as wired for sound quality? Should be possible, but I have not noticed anything so far (though I have not investigated thoroughly) so dunno if any like that?
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"The headphones have to have some sort of power. It would be batteries...
So either the phones would be really heavy to last, or, you would be changing batteries every few days."

You could keep the batteries in a separate pack and just run a power cord to the headphones. And use rechargeable batteries.
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