how to make cable with attenuation?

Discussion in 'Pro Audio' started by Vedran, May 13, 2005.

  1. Vedran

    Vedran Guest

    Can somene tell me how to make cable with 20db attenuation?
    Have to connect line balanced output to mic input of some portable reporter
    boxes.
    thank you
    Vedran
     
    Vedran, May 13, 2005
    #1
    1. Advertisements

  2. We are working on a project where we connect an audio card output to the
    input of the card.
    We are simply using a 10k and a 100k resistor to make a voltage divider.
    If You want it to be exactly 20dB You will have a problem with the input and
    output impedances of the system, but thats not really a problem in our
    application.

    By the way. How have You determined that it needs to be attenuated by 20dB ?

    /Jakob
     
    Jakob B. Olsen, May 13, 2005
    #2
    1. Advertisements

  3. Vedran

    Julian Guest

    Don't you need more than 20 dB attenuation to get line to mic level? You
    say boxes, plural. If there is more than one box that would change how you
    design it.

    For one box you can make a simple voltage diver by putting a resistor in
    series with the hot and then one across the minus and take the output across
    the parallel resistor. The series resistor will be higher in value than the
    parallel one. You should be able to find the values online for whatever
    attenuation you need. If you want to split this to several devices, you
    should also put an additional resistor on each plus and minus leg feeding
    the boxes, such that the sum of all the "build out" resistors equals the
    total input impedance.

    Julian


    OUT (high level) IN (low level)

    hot -------X X X--------- hot
    X
    X
    minus -------------X--------- minus

    ground------------------------ground
     
    Julian, May 13, 2005
    #3
  4. Vedran

    Arny Krueger Guest

    Just pick up a Shure or Audio-Technica mic attenuator. They
    have 3 levels of attenuation, one of which should be
    suitable.
     
    Arny Krueger, May 13, 2005
    #4
  5. Vedran

    Julian Guest

    Nice web page, Ethan

     
    Julian, May 13, 2005
    #5
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.