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Car PA system

  1. May 3, 2010 #1

    Can someone tell me if my idea is workable or not.
    I need to install a PA system in one of my training cars. Just the PA. No sirens, horns or whistles.

    My idea is to use a simple setup: mic- car amplifier - speaker (100W)

    The question is, can any mono car amplifier be used for this project?

    I am thinking of this one in particular
    http://www.fixya.com/recommendations/p75473-jbl_bp150_1_car_audio_amplifier [Broken]
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. May 4, 2010 #2
    You can use a car amplifier, but you would need a pre-amp to bring your mic output to line level for the amplifier to use. Also, the Amp you have in your link wont work at all, its a subwoofer amp, you need a full range amp. If you look at a few CB radios, most of them have a PA function built in, it would probably be cheaper. Also, in case you didn't know in most places its illegal to use a PA system on the street.
  4. May 5, 2010 #3

    Thank you for your answer. I will keep in mind your advice.
    As for the the PA system, is not to be used on public road but closed driving course.
  5. May 5, 2010 #4
    Old CB radios often had a PA output, I bet you could buy one on eBay for next to nothing, the speaker output is 8 ohms so you can go right to a PA speaker
  6. May 6, 2010 #5
    The CBs don't put out more than 30-40W to the speaker. We need 150-200W
  7. May 9, 2010 #6
    Not with a horn speaker. Horns are amazingly efficent, trust me 30-40W will be plenty. Just for reference, one of those bullhorns they use in sports etc. are only around 10-15 watts and they will make you go def.
  8. May 9, 2010 #7


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    I SERIOUSLY doubt any CB ever put out more than 3 to 4 watts on PA mode. 30 to 40 is unlikely.
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