Radial Engineering SB-1 ACTIVE Active Direct Box For Acoustic GuitarMade to fit inside a guitar case, the SB 1 is the smallest Radial DI box ever! But don't let the small size deter this ultra compact StageBug sounds absolutely terrific! The design begins with standard " instrument input with a thru put to feed your tuner or your on stage amp. The ultra quiet active circuit at once converts the signal from high to low impedance to reduce susceptibility to noise. The signal is then buffered and balanced for long cable