Convert line level to mic level

Discussion in 'Homework Help' started by Man_in_UK, May 15, 2008.

  1. Man_in_UK

    Thread Starter Active Member

    May 13, 2008
    Anyone know this ?

    What resistance should I add to a line level cable to make it suitable to plug into a mic level input ?
    Does the resistor go in series with the signal, or signal to ground ?

    I know the "correct" way to do this would be with a suitable transformer but reducing the signal will do.

    A friend wants to connect a DJ mixing unit to his laptop, only the laptop only has a mic input.

    Cheers loads in advance.
    Last edited: May 15, 2008
  2. JoeJester

    AAC Fanatic!

    Apr 26, 2005
    Some laptops have dual purpose inputs. Mine, for instance, whenever I plug in the microphone, a popup asks me if it's mic input or line input.
  3. Audioguru

    New Member

    Dec 20, 2007
    Two resistors in series with one grounded make a voltage divider. The line level signal to one end and the attenuated signal is across the lower resistor. Try 10k in series with 390 ohms to ground. Then the 150mV line level is attenuated to a 5.6mV mic level signal.

    If the line level is 0.5V then the attenuated signal is 18.8mV.
  4. Man_in_UK

    Thread Starter Active Member

    May 13, 2008
    Cheers guru. The complete solution in one hit.