According to lines of code spotted by MacRumors in Apple’s latest audioOS 27 beta 8, the company would be working on a feature allowing several of its HomePod speakers to be synchronized, notably to form a Home Theater system.
Apple HomePod: surround sound and automatic calibration
More specifically, this system consists of four units: front-right, front-left, rear-right, and rear-left. The code refers to automatic room calibration, speaker position mapping, timing adjustment, bass settings, EQ, dialogue enhancement, and different modes for movies and music.
Apple HomePod: a Party mode for music
Also mentioned is a Party Mode that would make it possible to pair two HomePod speakers to form a stereo system offering a more diffuse sound field, in order to distribute sound more evenly throughout a room.