Yes, as long as you're not looking to use the Streambar as a soundbar to get audio from antenna channels or other devices connected to the TV. For that, you'd have to connect the Streambar to an HDMI ARC input on the TV if it even has one. You'll get audio through the Streambar for any Roku channels/apps you use and for any other device (e.g., Blu-ray player) you'll get audio through the TV's speakers. It's also possible that your Roku 2 was connected to an ARC port on the TV and then you're good to go.
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