TopicPosted on 12/23/2015 at 10:54:21[Getting started] Understanding Impedance
There's no way to get around impedance when looking at speaker specs. Its rating is important to avoid frying up your amp, but also because the small details of an impedance curve reveal a lot about the performance of a speaker.
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angelie
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2Posted on 12/23/2015 at 22:53:22
Good article very clear written but i have one point / question
Quote:
in practice, the general rule is that you can connect two identical 8Ω speakers in parallel to an amp output rated at 4Ω, and three to an output rated at 2Ω.
You need 4 x 8ohm speakers to get to a value of 2ohms in total.
Or did you choose the number 3 to be on the save side?
Thank you for your comment and sorry for the delay,
your question is exactly the point where I run short of scientific explanations, indeed. I place myself from a practical point of view. It is true that I preferred being cautious when I gave advice to plug only 3 x 8 ohm speakers in parallel on an amp output that can stand 2 ohm.
Depending on the amp quality, the scientific rigour of the measurement of the impedance of the speakers and the conditions of use, plugging more than 3 is running a risk of an amp failure because of heat. But to be honest, I did use 2 x 4 ohm in parallel on a 2 ohm rated amp output, without any problem for the time of a concert. Nevertheless, prudence is a good guide.
With impedance, everything is about a ratio between the output and the input, I believe that depending on the quality of the amp, the security margin can vary between set-ups, even though they have the same ratings.