Conversion from 4 ohm to 8 ohm

Enzo Bretzer Posted messages 3 Status Member -  
georges97 Posted messages 14566 Registration date   Status Contributor Last intervention   -
Hello

I have an amplifier with an 8 ohm output and 2 speakers of 4 ohms each. Is there a way to connect them?

If I connect them simply in parallel, are there any risks: for the amplifier / for the speakers?
Best regards
Enzo

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3 answers

  1. georges97 Posted messages 14566 Registration date   Status Contributor Last intervention   2 919
     
    Hello,

    It is risky to connect 4 ohms speakers to an 8 ohm amplifier output. Some sites indicate that you can do it, provided you monitor the power, meaning not to push it to the max. And of course, they absolve themselves in advance of any consequences.

    In any case, if you wanted to achieve 8 ohms, you would need to connect the two speakers in series and not in parallel, that is to say by connecting the positives and negatives of both speakers to one channel (left or right). Thus, you would be missing the two same speakers on the other side. This is without considering the bandwidth alterations (audible frequencies) created by this setup.

    Some amplifier classes (there are classes A and B) are protected against short circuits caused by too low an impedance, but these are more likely professional amplifiers, which I am not familiar with and would cost you more than getting suitable speakers.

    Best regards.
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  2. Enzo Bretzer Posted messages 3 Status Member 2
     
    Thank you for the advice
    So, if I connect them in series and lower the volume, "will it work"?
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  3. georges97 Posted messages 14566 Registration date   Status Contributor Last intervention   2 919
     
    If you connect in series (one plus connected to the ground of the other speaker to end up with one plus on one side and one minus on the other side of the pair formed by the 2 speakers in series), you will have 2x4 ohms, so eight ohms, but this only applies to one channel.

    You are missing two other identical speakers on the other channel. Therefore, you would not have stereo and one channel would be empty.

    As for the volume, since you would have eight ohms in series, the problem would not arise, as long as the power of the speakers, in RMS watts and not marketing or musical, matches that of the amplifier (you have not indicated either one).

    For me, it is unachievable and risky with the equipment you have.
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