New Lossless and Spatial Audio Features Have been Added in HomePod 15.1
Apple Music is now compatible with lossless audio on the HomePod and HomePod mini thanks to the new update. As a result, when you play Apple Music on your HomePod, the device will play the lossless ALAC encoded stream rather than the lossy AAC encoded version. To use this feature, make sure the individual or family plan, not the new voice plan, is selected in the phone’s settings.
Additionally, Dolby Atmos support is now available on the larger HomePod only, not the smaller HomePod mini. Even if you only have one HomePod, you can use spatial audio, but the effect will be enhanced if you have two. Apple Music, Apple TV+, and the iTunes Store all offer Dolby Atmos-enabled content.