Experience powerful sound in any location with the D2A Audio Radiance-1 Loud Portable Bluetooth Speaker. It features patented Sound Emergence® technology, a unique and patented technology that reproduces the stereo sound in a new way, so it feels like live performance at a concert hall. Stereo, Surround Sound, and some 3D algorithms, all attempt to bring you closer to the live performance experience, but none gets this close. What makes a live performance in an acoustically perfect concert hall so great is the clarity, the loudness, and most importantly, the uniformity of the audio anywhere in that room. It also features a 3.5mm stereo input jack so you can connect music instruments such as guitars, keyboards, portable DJ setups, and smart home devices. The Radiance-1 provides more than 12 hours of playtime on a single charge and charges in around 2.5 hours.