GMF Ai1 Acoustic Preamp and D.I. - Direct Box For Guitar and Other Acoustic Instruments - 3in1 Analog DI Box, Direct To Amp Preamp and EQ, Headphone Amp DESIGNED SPECIFICALLY FOR ACOUSTIC PLAYERS. The Ai1 features a huge variety of control to shape the sound as well as other features simply not found in other acoustic Preamp/DI's. The compact size is great for travel, will fit in most guitar cases. FIRST it's a direct to amp preamp/EQ that sounds good straight to amp and has plenty of headroom and adjustment. SECOND it's a headphone amp!! Perfect for late night jams or when an amp is not available. The unit is self- powered to receive a headphone connection. Hook some effects pedals in line, Delay, Reverb, Chorus, etc., it really starts to come alive. THIRD it's a direct box!! DI balanced output for going straight to a board or mixer and an unbalanced Line Out, perfect for driving a powered cabinet. Now you can have your acoustic going direct to a mixer or mains without the hassle of mics! IN ADDITION there is a "stereo" Line In, so a music source can be added to play music or backing tracks from a tape/CD/Mp3 player, I-Pod or I-Phone and mixed into "all" of the outputs. (Direct Out/Line Out/Headphones) There is also a "stereo" Line Out feature which allows you to patch the Ai1 into a home or car stereo system so you can play your acoustic instrument without an expensive amp.