Sub 4 is the full-size wireless subwoofer in the Sonos lineup, and it exists to do one thing well: add the bottom two octaves that a soundbar physically cannot produce. Two 5 by 8 inch elliptical woofers face each other inside a sealed-and-ported cabinet, moving in opposite directions so their mechanical forces cancel. The result is output down to 25 Hz with almost no cabinet vibration, which is why Sub 4 can sit on a hardwood floor next to furniture without buzzing or rattling.
Each woofer gets its own Class-D amplifier, and the whole system is tuned by Trueplay to the room it lands in. The distinctive open-center form is functional as well as visual: Sub 4 stands upright beside a media cabinet or lies flat underneath a sofa or console, so placement is driven by acoustics and layout rather than by cable runs.
Connection is over WiFi, with 802.11ax support for a more reliable link on busy networks and a 10/100 Ethernet port if you prefer to hardwire. Setup is handled in the Sonos app, which assigns Sub 4 to a room and rebalances the crossover of the paired product automatically. Sub 4 works with Arc Ultra, Arc, Beam (Gen 1 and Gen 2), Ray, Five, Era 100, and Era 300.
Key Features
- Dual force-canceling 5 x 8 in woofers with dual Class-D amplifiers
- Frequency response extending to 25 Hz
- Mounts vertically or lies flat under furniture
- WiFi 6 (802.11ax) capable plus 10/100 Ethernet
- Trueplay tuning and app-guided setup
Why Buy This From 4TEC Direct
4TEC Direct is an authorized Sonos dealer, backed by 4TEC Integration — the commercial AV design and installation firm we have run since 2003, with over 35 years of combined experience in commercial AV design, programming, and sales. The people who answer your call are the same engineers who scope conference rooms, training centers, and whole-home audio systems every day.
- Authorized Sonos dealer — genuine, factory-fresh product with full manufacturer warranty
- Certified designers and programmers on staff — CTS, CTS-D, and CTS-I credentialed
- Free pre-sale system design — call before you order and we will spec the right zones, amps, and speakers
- Professional installation and 24/7/365 managed support available through 4TEC Integration
- Serving clients since 2003 from Omaha / Gretna, Nebraska — shipping nationwide
Questions before you buy? Talk to a real AV engineer: 402-909-0130 or sales@4tecdirect.com.