When the second generation echo devices were launched, the Echo Sub was launched along with them. This addition brings boom into your music quite literally. Here is my review of the Echo companion
Echo Sub review: All about that bass and we're delighted Review
Echo Sub Review: An Affordable Subwoofer for Compatible Echo Devices
Echo Sub Review: Alexa, Goes Boom!
Echo Studio review: smart wireless speaker with 3D audio skills
Echo Sub review: Add some serious bass to your Echo or Echo Plus speakers
Echo Sub Review: Alexa Brings the Bass
Echo Sub review: Exactly what you need for Alexa-powered music
Echo Studio review: Better than ever, but is that enough?
Echo Sub review: Exactly what you need for Alexa-powered music
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