Axiom Home Page Forums General Discussion Home Theater Wiring two speakers to one binding post

I have read that it is better to wire the speakers in series than in parallel, as that will lead you to double the impedance rather than half it. This will actually make the load on your amp much easier than before, but they will need a 3dB boost in level (that's double the power) to overcome the extra resistance.

To wire in series, connect the receiver's positive to speaker 1's positive, speaker 1's negative to speaker 2's positive, and speaker 2's negative to the receiver's negative. This is much safer for the amp than wiring in parallel.

-Cooper

Hi,

Not a good idea to wire speakers in series except for non-critical applications, because when you do, the impedance curves of the two speakers interact with each other causing potential changes in frequency response, none of which are desirable.

It's true that it will be an easy load for your amplifier, but it comes at the expense of good performance. Keep in mind that all impedance ratings of speakers are "nominal"--a kind of average. Few loudspeaker impedance curves are a nice straight line. In most cases, impedance varies with frequency across the audible spectrum, and it's those variations that will interact when you connect speakers in series.

Regards,

Alan,

Thanks for the explanation. So is that to say that the impedances of individual speakers wired in parallel will not interact in such a way?

kcarlile,

Here's the page at audiovideoreviews.com where you can see the NRC measurements of the M80ti, including its impedance vs frequency curve, which is very smooth. Sorry I don't know how to do the link thing:
www.soundstagemagazine.com/measurements/axiom_m80ti/

If you want to check out other loudspeakers, go to audiovideoreviews.com, then select Home Loudspeakers, find the speaker in the list that has "NRC" after it, then click on the measurement logo at the top of the review and scroll down to the impedance measurements.

In contrast to the M80s relatively smooth curve, take a look at the impedance curve of the M2i, which varies all over the place. This illustrates how impedance has nothing to do with sound quality or a smooth and even frequency response. The M2i's frequency response is very smooth and linear, whereas the impedance curve is quite variable.

Regards,

Does this (the variable impedance curve) that it would be inadvisable to wire the M2s in parallel?

Badger98 and kcarlile,

Correct. The impedance curves of speakers wired in parallel will NOT interact in the manner of series-wired speakers. So it would be okay to wire two M2i's in parallel so long as the receiver or amplifier will drive the lower impedance presented by the two speakers in parallel. The individual frequency responses of the two M2i's will be unaffected by paralleling them.

Regards,