Millions of people have incorporated Alexa into their daily lives, and Amazon continues to come out with new Alexa-powered speakers. Amazon announced a new iteration of its flagship Echo speaker, the Echo 4th gen, and it’s strikingly different than any of the previous Echo models. What’s the difference between the 4th-generation Amazon Echo and its predecessor, the 3rd-generation Amazon Echo? We break it down in this guide.

The 3rd-generation Amazon Echo has that all too familiar cylindrical shape. The unit measures 5.9 inches tall and 3.9 inches in diameter. It weighs 27.5 ounces, and it’s covered in fabric around the outside. You can choose between charcoal, heather gray, and sandstone color options. On top of the Echo 3rd gen sit four buttons — the volume up and down buttons, action button, and the microphone off button for when you don’t want Alexa listening. A light ring is located around the top perimeter, and it lights up in different colors to let you know what’s going on with Alexa.

The Echo 4th gen has a totally new design. It’s a spherically shaped device that’s just over 5 inches tall, and it measures 5.7 inches in diameter. At 2.14 pounds, the sphere weighs slightly more than the previous Echo, but it retained the fabric design. The Echo 4th gen comes in three color options: Charcoal, glacier white, or twilight blue. Aside from the spherical shape, another major difference between the Echo 4th gen and its predecessors is the location of the light ring and buttons. The light ring is located around the bottom perimeter, as opposed to along the top. The Echo 4th gen has raised buttons (mic off, action, and volume buttons), but they’re on top of the rounded sphere, instead of on a level surface like the previous generation.

The 3rd generation Echo already has good sound quality, as it boasts Dolby powered speakers with 360-degree sound. It has a 0.8-inch tweeter, a 3-inch woofer, and a 3.5mm jack for connecting other audio sources. If you’ve ever heard the 3rd-gen Echo, you know sound is one area where the device thrives.

The Echo 4th gen also has Dolby audio, as well as a 3-inch neodymium woofer. However, the newest iteration has two separate 0.8-inch tweeters for even better sound. The woofer is also upward-firing. And, like the Echo Studio, the Echo 4th gen can sense the acoustics in a space and tune audio playback accordingly. This should provide an optimal audio experience — even better than what you’d get with the Echo 3rd gen.

The Echo 4th gen is powered by Amazon’s first-generation AZ1 Neural Edge processor, which means Alexa should be faster, better, and more responsive than ever before.

The 3rd-gen Echo looks a lot like its cousin, the Echo Plus 2nd gen, as the Echo and Echo Plus speakers have been getting closer and closer in terms of their design and features. The newest iteration of the Echo combines the Echo and Echo Plus into one device.

The Echo 4th gen has a built-in hub, which is something the previous generation Echo lacked. With a built-in Zigabee hub and temperature sensor, you can easily set up and manage compatible devices, as well as set commands and routines related to temperature.

New Echo devices, like the Echo 4th gen, receive the “Climate Pledge Friendly” badge on Amazon. Amazon is using materials like post-consumer recycled fabric and recycled die-cast aluminum to make its devices more environmentally friendly. The brand is also including other features to promote energy efficiency, like low power modes and an energy dashboard to help you see power consumption across your Echo and smart-home devices.

The Echo 3rd gen is available on Amazon as a refurbished version for $90.

The Echo 4th gen releases on October 22. It costs $100, and you can pre-order the device on Amazon today.