Impedance Matching Transformer?

Discussion in 'General Electronics Chat' started by RJ31X, Aug 20, 2014.

  1. RJ31X

    Thread Starter New Member

    Aug 20, 2014
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    I have a whole house music system, which requires, 25 ohm speakers. I have two blown outdoor speakers, which I would like to replace with Bose 151 4ohm speakers. Can I use an Impedance Matching Transformer? I have some experience, but need some advise on which one to use and how to basically connect it.
     
  2. Lestraveled

    Well-Known Member

    May 19, 2014
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    Interesting..... I could not find any one selling a 25 ohm speakers, nor any whole home music system that uses 25 ohm speakers. Are you sure it is a 25 ohm system?

    Do your speakers have matching transformers built on them?
     
  3. adamclark

    Member

    Oct 4, 2013
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    6
    most house systems are 8 ohm configurations,, I am an automotive electric tech. and I have used transformers to change impedance in extreme situations.. although you do raise your impendance you sacrifice ALOT of power doing so.. are you able to series 2 8 ohm speakers per side to end up with 16 ohms,,series a third one in there and you get 24 ohms
     
  4. RJ31X

    Thread Starter New Member

    Aug 20, 2014
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    yes 25 ohm no matching transformer. the system is M&S Music & Sound they were bought out by Linear corp
     
  5. ronv

    AAC Fanatic!

    Nov 12, 2008
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  6. crutschow

    Expert

    Mar 14, 2008
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    Yes, it sounds like a 25 volt system, which uses a transformer at each speaker, not a 25 ohm system.
     
  7. RJ31X

    Thread Starter New Member

    Aug 20, 2014
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    no! I know ohm's law. I learned it 40 years ago, and I can read.
     
  8. RJ31X

    Thread Starter New Member

    Aug 20, 2014
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  9. RJ31X

    Thread Starter New Member

    Aug 20, 2014
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    Thanks for the reply. all reply's so far are telling me I do not know what I am writing. I have been doing electrical work for forty years. I hold a state contractors license, and I went to school for electronics, and I can build computers. I am not a genius, but I am also not stupid.
     
  10. ronv

    AAC Fanatic!

    Nov 12, 2008
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    We are not questioning what you are writing. But maybe what you are reading.:D 25 volt systems are often used for long runs from the amplifier and require a special amp. Kind of sounds like you.
    Can you show a picture of the bad speaker that makes you think it is 25 ohm?

    Try looking at Nu Tone speakers.
     
    Last edited: Aug 22, 2014
  11. Externet

    AAC Fanatic!

    Nov 29, 2005
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    Yes, you can use an impedance matching transformer 25:4, with the 4 ohm winding connected to the speaker.
     
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  12. RJ31X

    Thread Starter New Member

    Aug 20, 2014
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    Nutone outdoor speakers are 45 ohm. I could connect two in parallel, but they are only weather resistant, not proof, which I need. Thanks anyway
     
  13. alfacliff

    Well-Known Member

    Dec 13, 2013
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    the system is an intercom system, those use special made high impedance speakers so they work as microphones. I dont know of a source for 24 to 4 ohm impedance transformers.
    if you use a 25 volt audio transformer connected to the d25 watt tap, it will match 4 ohms to 25 ohms.
     
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  14. djsfantasi

    AAC Fanatic!

    Apr 11, 2010
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    Google is your friend. "25 ohm speaker" turns up many hits; including this one from NuTone.
     
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