Since we both possess excellent hearing I've never wanted to spend more than a token amount of money on a tandem intercom. As a result I've flirted with some seriously cheesy wired things and not much more. The recumbent tandem we recently bought puts our heads more than twice as far apart as on any of our upright tandems. I'm thinking an intercom will be useful going forward. I've researched most of what is available now. Nothing jumps out. But I'll tell you what looks interesting: Smartphones. We both have iPhone 5s's and audio Facetime conversations would not use cell minutes which are unlimited in any case. As a proof of concept I bought a pair of these: https://aftershokz.com/collections/w...anium-with-mic. I've used mine several times on my single with my GPS and indeed you can hear the audio from the phone with unimpeded access to ambient sounds. Wireless options are available. We have not been out on the tandem though to do a real proof of concept trial run. I see no downsides though.