There are lots of things you can do with a spare Android phone: keep it as a backup, turn it into a baby monitor and so on.

Here's another: turn it into your very own Google Home ( ).

I'm referring, of course, to Google's smart speaker, which is a direct competitor to Amazon's widely beloved Echo. With a price tag of $129, a Home costs less than an Echo, but it's still an expensive piece of hardware.

Ah, but what if you could cobble together the next best thing using gear you already own? You can!

Old gear, new 'Home'

LuguLake

This is pretty straightforward: You're going to repurpose an old Android phone and pair it with a speaker. The former will net you Google Now, while the latter gives voice to its responses.

First, let's talk about the gear, then look at what you can -- and can't -- do with this kind of setup.

The phone is fairly easy. All you need is a relatively recent model, one with an updated Android OS and the latest version of Google Search. Ultimately, the key requirement is support for "OK, Google" detection. Stay tuned for more on setting that up.

As for the speaker, anything you can connect your phone to is fair game. My recommendation is a simple Bluetooth speaker, though it has to meet one requirement: It needs to stay powered on when plugged in. Some speakers have an auto-off feature, which you don't want here.

You can also take the wired route, plugging one end of a 3.5mm audio cable into your phone and the other into a speaker or even an old stereo. It's one more wire you'll have to look at, but of course a little decor disguising can help with all the wires.

Speaking of which, you'll need to leave your phone plugged in full-time, same as the speaker.

Obviously all this won't provide the same pretty aesthetic afforded by a real Google Home, but functionally it'll get reasonably close. And if you want to keep everything in close proximity, consider getting a speaker that's also a phone stand. For example, the LuguLake Bluetooth speaker/phone stand shown here might prove a good option, if only because it gives your phone a forward-facing place to sit. It's currently priced at $29.99.

Enlarge Image Screenshot by Rick Broida/CNET

Although you'll have to provide the wall USB plug for the speaker to stay powered, it has a physical on-off switch, so I'm pretty certain it won't automatically shut off after a period of inactivity. (Not positive, though; check with the manufacturer if you want to be sure.)

Give Google ears

From there you simply need to power up the speaker, pair the phone with it (via cord or Bluetooth) and make sure the phone is configured for voice detection.

Depending on the model and which version of Android/Google Search you have, this may already be set up correctly. On my Samsung Galaxy S6 ( ), for example, which is still running Android 5.1, I needed to venture into the Google app's Settings menu, then tap Voice > "Ok Google" detection and make sure "From any screen" was enabled.

With that done, Google would be listening for spoken commands even when the screen was off -- so long as the phone remained connected to power.

Talk the talk

Now it's time to say those magic little words: "OK, Google." If you're already acquainted with this feature, you know the drill; the only variable here is now there's a "permanent Google" connected to a speaker.

(What about your current phone? Isn't it listening as well? Sure enough, your spoken commands might trigger both phones at the same time. The Google Home, for its part, is location- and context-aware, and prioritizes spoken commands.)

So what can you do with your new "Google Home"? Pretty much anything and everything you can do with your phone, natch. That's both good and bad, because Google's voice-activated assistant works a little differently across different kinds of devices -- and not always for the better in this case.

For example, you can say, "OK, Google, play some Billy Joel on Spotify," and it'll open up the Spotify app and queue up a playlist -- but stop short of actually playing it. That's a bummer, because you'll have to manually start the music, kind of defeating the purpose. (Substitute "Pandora" for "Spotify," though, and you'll get your tunes, because the former auto-plays when you launch it.)

Enlarge Image Tyler Lizenby/CNET

You can also ask for specific songs or albums that are in your Google Play Music library, but if you're not a subscriber to the eponymous streaming service, you might not be happy with the results. My spoken requests to play certain albums or artists were often met with failure.

When I asked for some Adele, for example, Play Music tried to play songs not in my own library -- and couldn't. Keep in mind, though, that this is all based on Google Now as opposed to Google's newer, smarter Assistant, which may be able to do a better job fielding music requests. Unfortunately, for the moment only newer phones have access to Assistant. (Here's how to see when Assistant might be coming to your phone.)

Fortunately, Google Now can handle a wealth of other handy tasks. It can answer all kinds of questions, set alarms, give you news and sports updates and much more. It can also make phone calls for you (provided the phone still has service or you've set it up for Wi-Fi calling) and send messages, neither of which the Google Home can do.

Despite the rather frustrating music limitations, a home-brew Google Home can be a nice addition to your pad. And it's definitely a cool way to put an old phone to good use. Your thoughts?

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