The Sonos Sub (Gen 4) is engineered for those who want to elevate their home cinema and music experience with professional-grade bass. Specifically designed as the perfect pairing for the Sonos Arc Ultra soundbar, it transforms a living room into a theater by adding deep, rumbling low-end delivery that reaches frequencies as low as 25Hz, making Hollywood movie soundtracks feel truly immersive. At the heart of the Sub (Gen 4) is a sophisticated internal design featuring two opposing drivers. This architectural choice effectively cancels out distortion, ensuring that the bass remains clean and impactful even at high volumes. While it maintains the same physical dimensions as its predecessor—roughly 40cm square and 16cm deep—it features a redesigned internal porting system and is marginally lighter at 11.79kg. One of the most noticeable upgrades is the new matte exterior finish. Unlike the glossy finish of previous generations, this matte surface is significantly more resistant to fingerprints, maintaining a clean, premium look in any room. The design is further distinguished by a centralized opening that allows for a unique aesthetic and acoustic profile. Integration is seamless within the Sonos ecosystem. Using the Sonos app, users can easily pair the subwoofer with their soundbar and fine-tune the audio experience by adjusting the bass output by +/- 15 levels or toggling the subwoofer off for late-night viewing. For those seeking an extreme audio environment, the system supports pairing two Sub (Gen 4) units with a single soundbar. While it represents a premium investment, the Sonos Sub (Gen 4) is the 'boss of bass' in the Sonos lineup. It is an ideal addition for users building a new high-end system or those upgrading from smaller Sonos speakers who want a sea of bass that you can feel as much as you can hear.