Purpose
The Direct Input box takes a high impedance, unbalanced signal and converts it to a low impedance, balanced signal.
This allows the signal to be sent over long cable runs with significantly less signal loss (especially in high frequencies) due to the lowering of the impedance, and greater rejection of interference due to the benefit of common mode rejection in a balanced signal. Furthermore, the lower impedance (around 600 ohms is normal) allows an insignificant load to the input of a mixing console or preamp which is also designed to accept input from low impedance microphones.
Read more about this topic: DI Unit
Famous quotes containing the word purpose:
“Respect is not fear and awe; it...[is]the ability to see a person as he is, to be aware of his unique individuality. Respect, thus, implies the absence of exploitation. I want the loved person to grow and unfold for his own sake, and in his own ways, and not for the purpose of serving me.”
—Erich Fromm (20th century)
“The purpose of polite behavior is never virtuous. Deceit, surrender, and concealment: these are not virtues. The goal of the mannerly is comfort, per se.”
—June Jordan (b. 1939)
“The technologist was the final guise of the white missionary, industrialization the last gospel of a dying race and living standards a substitute for a purpose in living.”
—Max Frisch (19111991)