The best sound. Whenever you need it. The radial stagebug sb 4 active piezo di box is the ultimate companion for your violins cellos and other instruments equipped with a piezo pickup. Whether youre on stage or in the studio youll get crystal clear audio. No squawks. No peaks. And no feedback. Simple yet powerful control. Alongside its plug and play design the sb 4 is ready for any eventuality. Instantly correct phase alignment with the 180 degree polarity switch. Or quickly tame your low end with the high pass filter. Its all there. Right at your fingertips. Portable and practical. The sb 4 is designed to fit neatly into your instrument case. And with a robust construction youll never have to worry about knocks and drops getting in the way of your performance. This is the easiest way to guarantee professional sound.