Alexa is just the software that runs on any Echo (including the Dot), so when you get a Dot, you’ve got Alexa. Just think of it as the voice of Echo. You will need to download the Alexa app on your smart phone in order to set up your Echo or Dot.
All of the Echo devices come with Alexa. You wouldn’t need to buy anything extra—you can’t have one without the other. Alexa is just the name for the voice-control feature that the Echo products use. If you buy the Echo Dot and set it up, you could activate it by saying, “Alexa, play music,” and your Echo Dot would play music.
If you already have a digital library of classical music, you could upload some of it to your Amazon account and listen to it for free. If you have an Amazon Prime membership, you’ll be able to listen to a large amount of Amazon’s library for free. You could listen to music from your cell phone through a Bluetooth connection. Or you could use the Echo to connect with an online streaming service—many of which do charge a subscription, but many also have free versions if you’re willing to listen to advertisements.
There are no subscription fees unless you want to add Prime or a fee music service such as Spotify.
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