The LG S77S is a premium 3.1.3 channel soundbar featuring 400W total power output with a wireless subwoofer. This Costco-exclusive model features a unique rounded design with dual center channels - one front-firing and one up-firing - specifically engineered to enhance dialogue clarity. The soundbar supports Dolby Atmos and DTS:X for immersive three-dimensional audio with triple up-firing channels that deliver overhead sound effects.

Key features include WOW Orchestra technology that synchronizes audio between compatible LG TVs and the soundbar for an enhanced listening experience, controlled through a single remote via WOW Interface. High resolution audio support up to 24-bit/96kHz provides exceptional sound quality. AI Sound Pro uses deep learning algorithms to automatically optimize sound based on content type, delivering clear vocals in sports, enhanced bass in music, and dynamic sound in action scenes.

The soundbar includes HDMI eARC for lossless audio transmission, 4K passthrough with HDCP 2.3 support, Dolby Vision and HDR10 passthrough, and gaming features including VRR and ALLM up to 120Hz for smooth, lag-free audio. Additional features include Clear Voice Plus for improved dialogue clarity, Triple Level Spatial Sound for cinematic immersion, Smart Up-Mixer to convert 2-channel audio into multi-channel surround sound, bass and treble adjustments, and multiple sound modes including Cinema, Music, Sports, Game, and Bass Blast. Wireless connectivity via Bluetooth and smartphone control through iOS/Android app. Compatible with TVs 40 inches and larger.