Editors' Note, January 31, 2017: Thanks to Amazon's ESP feature, you no longer have to worry about device overlap since only the closest Echo will respond to you if multiple devices hear your command. The second half of the piece has been updated to reflect this change.

It's time to think big picture now that we've reviewed all three devices with Amazon's Alexa virtual assistant. What if you want to roll out Alexa to every room in your house?

A quick refresher: Alexa is the speech-recognition technology built into Amazon's Dot, Echo and Tap smart speakers. Alexa is programmed to respond to a wide variety of voice commands. She can tell you the weather or the news, she can add an event to your calendar or you can use her to make a shopping list. Alexa can play music from streaming services such as Spotify, Pandora and, of course, Amazon Prime. She can also control an impressive list of smart-home devices. Thanks to an aggressive expansion plan from Amazon, Alexa gets support for new products and digital services weekly.

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Meet the Alexa Family

Amazon Echo: The original $180 Alexa device has a robust speaker for playing music, and an impressive wide array microphone that's always listening. Say the wake word "Alexa," even from the next room, and the Echo will hear you and respond.

Amazon Echo Dot: The $50 Dot is essentially an Echo with the speaker chopped off and an added audio output port and a Bluetooth radio. It's still always listening, and it will still play music on its own, but the sound quality is more like that of a smartphone. Thanks to the audio output and Bluetooth, you can connect it to your own speakers or home entertainment system. It earned out Editors' Choice award in October and is our favorite Echo device.

Amazon Tap: The third member of the Alexa family, the $130 Tap trades always-listening convenience for battery-powered portability. You have to hit a button to talk to the Tap, so you don't need to use the Alexa wake word, but you still have access to all the same Alexa functionality once you start talking. The lightweight Tap can work like a typical, portable Bluetooth speaker. Connect it to the internet and it can stream music and let you use Alexa on the go. Since it's not always listening, the Tap is our least favorite Alexa device, and the only member of the Echo family we don't regularly use in the CNET Smart Home.

In addition, Amazon has two other Alexa-related products:

Voice Remote for the Amazon Echo: A $30 Bluetooth remote that connects to your Echo or Echo Dot, allowing you to give commands beyond standard listening range. You need to push the button on the remote to talk. It does not work with the Tap.

Fire TV Voice Remote: Included in the $50 Fire TV stick bundle or as part of the full-sized $85 Fire TV, it allows you to control your TV with Alexa with the push of a button, similar to the Tap or the Voice Remote. It only works with your TV, so I won't address this device when discussing how to best outfit your home with Alexa.

How Alexa devices work together

It's surprisingly easy to add multiple Alexa devices to a single Amazon account. The Amazon Alexa app for iOS and Android walks you through the process. If you sync control of any smart home devices to one Echo unit, any other Echo products tied to the same account will also recognize them.

Enlarge Image Tyler Lizenby/CNET

Thanks to an audio line-in on the Tap and the magic of Bluetooth, you can link the Tap to the Dot either over a cable or wirelessly. This combination gets you the better speakers and the portability of the Tap with the always-listening Alexa feature via the Dot. Buying both the Dot and Tap will cost $180, the same as a single Echo, and it gives you a more flexible set up with portability when you need it -- and always-on Alexa convenience when you don't.

Another way to extend Alexa is a single Echo and a Voice Remote. That will cost $210 and it will give you the best speaker of the set, plus an Alexa contact point in one room. The Voice Remote uses Bluetooth, and I was impressed by the range when I tried it out in the CNET Smart Home. I placed an Echo on the top floor, went one floor down into the basement, and the Echo still responded to my commands via the remote.

Enlarge Image Tyler Lizenby/CNET

The most affordable way to extend Alexa to multiple rooms is to buy the Echo Dot and extend it with the Remote. That setup will cost $80. This makes sense if you already have a speaker system for the Dot, or if you don't care about using Alexa for music streaming.

Alexa out of sync

Although adding multiple devices to your Alexa app is seamless, you can't combine two Echo devices to create a stereo effect or surround sound audio setup like you can with Sonos speakers. The Echo's main competitor -- Google Home -- does let you group speakers for synched audio, so Alexa's trailing behind here.

Putting multiple Echoes too close together used to lead to another annoyance -- if you told the Echo in your kitchen to play a song, the Dot in your living room might also have heard the command, and then you would get both speakers playing the same tune, but without syncing up.

Fortunately, as of last October, Alexa's ESP feature fixed that issue. Now, if you have multiple Alexa devices in hearing range, only the one that hears you best will respond. You'll need to have them all synched to the same account for this to work, so you could still get overlap if your kids or significant other have their own Amazon accounts and they're logged into one of your Echos.

The guidelines below will help you plan for complete coverage with minimal overlap. You don't need to be as cautious anymore, thanks to the ESP feature. If you do have a family member with a different account and an Echo device in an adjoining room to yours, simply switch the wake word for one of the units. In the app, you can program Alexa to respond to "Amazon," "Echo" or "Computer."

Picking your devices

The Dot is our favorite. It's the best, most affordable choice if you don't care about music quality and just want an always-listening assistant. It's also the best choice if you care a lot about the sound quality of music. In that case, you probably have your own speaker setup, and the Dot can just plug right in.

The original Echo's a fine choice if you want a virtual assistant, and a device to fill a large space with only decent-sounding music. $180 price tag aside, it's still the best stand-alone product of the bunch.

The Tap loses some of the charm of the other two since it's not always-listening. It's a good option if you want Alexa and a portable speaker in the garage or patio from time to time. That said, the Voice Remote is a cheaper way to fill in the gaps in if you just want to bring Alexa to the far corners of your home.

Recommended setup by house size

As always with planning out a smart home set up, your best bet is to start small with one or two Alexa devices to see how you and your family will really use them. Build out only once you get a feel for them.

Then, if you find yourself wanting to talk to Alexa in both the kitchen and the bedroom on a regular basis, put an Echo or a Dot in both rooms. It no longer matters how close the rooms are.

Use the following guidelines if you know you want a whole home Alexa set up.

Small homes, apartments (one floor; up to 1,000 square feet)

One always-listening Alexa device should cover it. Put either an Echo or an Echo Dot in a central spot in the room you inhabit most often, and you'll rarely be out of shouting distance. Both can pick up your voice through one closed door. Buy a Voice Remote if you have lots of interior doors, or to minimize yelling.

Medium homes (one to two floors; 1,000 to 2,500 square feet)

Most of the time, one Echo or Dot will be sufficient if you place it in a central room in a medium-sized home. One wall of separation is the limit if you want Alexa to clearly hear you, though, and you'll want to be in the same room if you want Alexa to hear you over music or the television.

I used to recommend a Tap for family members interested in a device in their own space near a center room, but now you can pick your always-listening device of choice.

The Tap still comes in handy if you want to take Alexa with you to work in the garage or out to the patio. Use a Voice Remote for any peripheral areas where you don't care about music, but you still want to issue commands to Alexa.

Large homes (two floors plus; more than 2,500 square feet)

In general, you'll be fairly well covered with one Echo or Dot per floor. Keep in mind the one wall guideline. If your home floor plan is wider than it is long, you may need more than one Echo device for full coverage.

If you find Alexa can't hear you over your TV, the best way to mitigate the problem is with the Voice Remote. For instance, you can place an Echo in the living room at one end of your main floor, hook a Dot into the entertainment center at the other end, and then place a Voice Remote in any areas in between and you'll always be able to give voice commands.

In general, Taps are better for moving between areas where you only want to play music on occasion, though it's not too much of a hassle unplugging and replugging the Echo or the Dot.