One SU (especially around the camera), but flip it around and you'll notice what appears to be a pair of front-facing stereo speakers (aka BoomSound as it's marketed as for the One), as well as the same dual soft key implementation on the company's latest flagship.

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Unlike other in-ear cordless solutions, each pair of stereo STRIVA TAPs does not require wires concealed in a headband to connect the left and right earpieces together.

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The two differ only in how they get their highs out, with the S350 including a pair of squat stereo speakers and the S400 offering a three-channel "air surround xtreme" soundbar.

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The company's rounding out its line up with a pair of audio devices, too -- the G430 and G230 surround and stereo gaming headsets.

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Nowadays we're spoiled with options in the Bluetooth speaker market, and many of the high-end ones -- especially those from Soundfreaq and Nokia -- even feature dual-system streaming (DSS) that lets one speaker pair with another to enable true stereo playback.

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