Hybrid Active preamp for Acoustic Guitar, Nanoflex and NanoMAG pickup/preamp combo for steel string guitar. Nanoflex pickups not only respond to string vibrations, but also sense the vibrations of the body of the instrument simultaneously. This completed shielded system incorporates active amplification in the pickup itself, which makes it 100% hum and noise free. NanoMAG pickups are low-impedance active mini-humbuckers made with Samarium Cobalt magnets. These innovative Shadow pickups are balanced for both acoustic and electric guitar strings and have a much larger frequency range than your typical midrange-heavy humbucker. The SH SONIC DP is an easy-to-install pickup system that houses its preamp elegantly in the endpin jack, which means no cutting into the side of the guitar. The volume and tone controls are mounted discreetly inside the sound hole along with the 9V battery pack/holder.