The consumer technology giant said Tuesday that the HomePod’s stereo feature is part of a larger update to the iOS mobile operating system that’s now available to download.

Apple said that when two HomePods are connected to play music in stereo, one speaker will act as the “left” channel while the other speaker will act as the “right” channel, similar to conventional stereo speakers. When linked, however, the speakers will “act as one” so that if a person asks Siri to play a song, both speakers will play the tune, Apple said.

Additionally, Apple (AAPL) said the new iOS update lets people sync together multiple HomePod speakers so that the play the same music from different rooms in their homes at the same time. This so-called multi-room audio feature is becoming popular with smart speakers with Amazon’s (AMZN) Echo speaker getting a similar feature last August.

It should be noted that with the HomePod selling for $349, people should expect to pay $700 or more for the stereo or multi-room features.

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Apple’s iOS update also includes a new version of Apple’s audio streaming technology AirPlay 2 that will make it possible for people to connect their HomePods to AirPlay 2-compatible speakers, which include certain models made by Bang & Olufsen, Denon, Marantz, and Sonos, Apple said. Although people won’t be able to sync a HomePod with a third-party speaker to play music in stereo, they will be able to play the same music through multiple speakers by asking Siri.

Apple first debuted the HomePod in February as the company’s flagship smart speaker. HomePod faces stiff competition from Amazon’s Alexa-enabled devices and the Google (GOOG) Home speaker. Technology reviewers have generally praised the HomePod’s sound quality, but criticized the capabilities of its integrated Siri digital assistant when compared to rivals.