Amazon Fire TV Cube
You can use an Echo to control your Fire TV and a universal remote. Or you could just buy an Amazon Fire TV Cube. The latest Alexa-enabled gadget, it combines the voice powers of the Echo with the streaming capabilities of the 4K Fire TV, while adding in an IR array to control everything from your legacy cable box to your soundbar. It can control your TV over HDMI, so it can turn it on and off as needed, whether it's to play a show or just show you additional information from Alexa.