re how do di boxes work in article lancer apr oconnor wpi edu lancer oconnor wpi edu stephe lewis foskett writes i m doing sound for a couple of bands around here and we need direct input boxes for the keyboards these are the little boxes that take a line level out of the keyboard and transform it into low z for the run to the mixer sadly they cost like or more each and i m going to need like or of them i looked inside one belonging to another band and it looks like just a transformer does anyone have any plans for building them perhaps in anderton s electronic projects for musicians book which i am having a hell of a time tracking down an easy way to solve the problem is to use two op amps to form the balanced low z output but this solution does not provide any galvanic isolation between keyboard or whatever plugged and mixer if no tight requiremets are demanded and some hum snap crackle and pop sounds formed by ground loops can be tolerated the op amp solution is just what you are looking for it is cheap somewhat di box not sure but craig anderton did introduce one di box project in guitar player mag years ago transformerless thanks a lot hope this helps email if more details wanted lancer wpi wpi edu modimidofrsaso mein kopf ist ein labyrinth mein leben ist ein minenfeld heikki paananen heke stekt oulu fi the university of oulu department of electrical engineering just a student finland home is where the heart lies but if the heart lies where is home fish
