Polarity issue


Hello all, I changed spade connections recently on a pair of anti cable spkr wires(Paul Speltz)and neglected to mark the plus and minus sides for the amp. The spades in question are not marked so I need a way to keep the polarity in sync. I have a radio shack meter and if anyone could assist me on what to do I would be most thankful. I have the wires twisted as recomended and most of the wire is inside my spkr posts for looks so tracing them from the spkr side is not an option. Thanks in advance and enjoy the music.
south43

Showing 2 responses by steve60a5

Couple of things you can do.

You can just connect the cables to the amp arbitrarily. Give them a listen, taking note of the bass response. Then reverse the leads at the amplifier for one channel. Listen again. If the bass increases, they're now wired in phase. If it decreases, they're reversed so flip the leads around on one of the channels.

If it's not a big inconvenience, this is best done with the speakers as close together as possible.

If you're also concerned about absolute polarity, and if the woofers on your speakers don't have a capacitor connected in series with them, you can take a battery, preferably a 9 volt but a D or C cell will work too, and hold one of the speaker leads to the negative terminal of the battery. Then take the other lead and touch it briefly to the positive terminal of the battery while taking note of what direction the woofer cone moves.

If the cone moves out, then the polarity of the leads are the same as the polarity of the battery, i.e. the lead you're touching to the positive terminal is the positive lead and vice versa.

If the cone moves in, then the polarity of the leads are opposite those of the battery.

se
If these spkrs are indeed connected via a cap would the battery test hurt anything?

No. The only problem with the cap coupling is that capacitors block DC which means the cone won't move and you wouldn't be able to determine the polarity using the battery method.

I may have to just unhook the spkr wires from the amp end and do the meter thing as suggested by the other Agon members.

You'll have to do that even with the battery test. Otherwise the amplifier's output will look like a short to the battery and all the current will flow through the amp rather than the woofer like it should.

Good luck!

se