An audio receiver amplifies the sound of the blood moving though the vessel.

有一个音频接收器放大血流通过血管的声音。

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In 1953, Harman and partner Bernard Kardon invented the first integrated audio receiver, ushering in the era of high-fidelity home stereo systems.

FORBES

If Roku let you sync up multiple remotes with a single box, each could serve as an ad-hoc wireless audio receiver for a room full of suddenly wireless speakers.

FORBES: The Roku 3 Set-Top Box: A Nearly Perfect Product

So provided that your speakers have their own power source, it's just a matter of charging these aluminum dongles up (a single charge lasts up to 10 hours), plugging them in and then pairing the right receiver with your audio source.

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