4 ohm speakers with amp rated for 8 ohms?

I'm replacing my very old Dynaco PAT-4/Stereo 120 amp that I use for my 4 ohm AR-3A speakers. I have a Sherwood RX-4109 receiver I want to use. The manual says to use at least 8 ohm speakers. It's rated at 100W/channel. I use them in a small space, so I'm not going to play them very loud.

Can I get away with this, or will the impedance mismatch possibly harm the receiver, or give me unsatisfactory performance?

5 Answers

  • khalil
    Lv 7
    1 month ago

    if you use a 8 ohms instead of a 4 ohms, the output power will go down .... 88.88%if you use a 4 ohms instead of a 8 ohms, the output power will go down .... 88.88%the speaker should stand the amplifier power otherwise turning up the volume will fry the speaker.

  • 1 month ago

    Personally, I would keep using the Dynaco equipment. 

    It's still very good stuff. 

    (I own a 120.) 


    As long as you don't crank the volume too high, 

    using 4 ohm speakers should cause no problems. 


    In case you didn't know or forgot, the optimum load for the Stereo 120 is 8 ohms. 

    I would find it hard to believe your 4 ohm speakers have hurt it over the years. 

    • nbsale
      Lv 6
      1 month agoReport

      Yes, I've liked the Dynaco set up ever since I bought it in 1972. But I have limited space, and I can replace 3 components, preamp, amp, tuner, with 1 decent receiver. Interested in adding a Kenwood KT-8300 high end tuner to your vintage set-up?

  • Paul
    Lv 6
    1 month ago

    I let my son use my AR-3A speakers with a cheap amp.  Burned out the tweeters.  Amps that are are compatible with 4 ohm speakers will say so in their specs.  They tend to be a bit pricy.

  • Tony B
    Lv 7
    1 month ago

    You should use at least 8 ohm speakers. The manual wouldn't say that if 4 ohm speakers were okay.

    Yes, you could damage the receiver. How likely it is that damage occurs is impossible to say.

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  • Joe
    Lv 7
    1 month ago

    You will probably get away with it.  Especially at modest volumes.

    If you play it loud, you might trigger the protection circuits.

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