Bill Evans of FOH magazine has covered personal monitors (also known as "speakers in your head") from that end of the signal chain a couple of times. But no matter how good your earpieces are, they are of no real use unless you have a wireless IEM transciever package that is at leaset as good as your ears. And in the post-700 MHz world, doing more in less bandwidth is just something wireless guys have to deal with. Here is some of the cooler stuff we have seen to help that happen.
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