Re: How to determine polarity of speakers

> I suspect that the 3-way Alpine SPX speakers that I had installed are
> not all in phase. Normally, to test polarity, I'd hook a 9volt battery
> up to the speaker wires normally going into the amp. Each speaker
> should either pop out or pull in, but all should do the same thing,
> assuming positive and negative are hooked up correctly.
>
> HOWEVER, these 3way speakers have not one but two crossovers that like
> to absorb the 9v and prevent the speakers from moving.
>
> How else can I test the polarity? Do I simply need to add more 9volts
> into the equation, and if so, how many, and how many would it take to
> accidentally fry my crossovers?

There are high pass crossovers in series with the woofers too?

Another way to do it would be to listen to the bass response, reverse the
leads of one speaker, and listen to the bass response again. Usually, but
not always, the bass response will be substantially higher when the two
speakers are in phase with each other.

A third way to do it would work if you have a simple voltage meter -
preferably an analog meter (I tend to say that a lot), but it usually works
with a digital meter as well. If you have access to the speaker wires
somewhere, either at the back of the radio or the amplifier (depending on
what it's hooked up to), you can measure the sign of the induced voltage
when you press the speaker cone. In other words, push the cone in (not so
far that you damage something) reasonably fast - the faster, the higher
voltage you'll measure - and have a friend watch the meter. Pushing it in
should make the needle either go positive or negative, and letting it out
should make it go in the opposite direction. Make sure it matches for both
speakers.


.

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