For the money i would say no, the echo second gen is a great little speaker. The echo plus obviously has more tech in it and is slightly louder but who listens to music full volume all the time.? Double the price does not give you double the sound.
You should have the app on a phone/tablet etc? If so, select devices (bottom right) then “echo plus”, then click top right (3 dots). You should now see the volume control. Note; there are a few ways to adjust volumes for the echo plus, I have found that Alexa volume increases/decreases now and again.
Tech spec shows it DOES connect to Wi-fi: "Wi-Fi Connectivity: Dual-band Wi-Fi supports 802.11 a/b/g/n/ac (2.4 and 5 GHz) networks. Does not support connecting to ad-hoc (or peer-to-peer) Wi-Fi networks."
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