Author Topic: Phase & Polarity Issues  (Read 1274 times)

Offline Superfly

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Phase & Polarity Issues
« on: October 18, 2005, 06:55:42 AM »
I thought it would be useful to give this post it's own thread, since it's an important issue for multi-cab users, and something which comes up in discussions fairly often...

Checking speaker cables for tip/tip conductivity...

Simply use a flashlight battery and a flashlight bulb. Press the bottom of the bulb against the top of the battery, and complete the circuit by pressing one tip end of your speaker cable to the bottom of the battery, and the other tip end to the side of the flashlight bulb.

If the bulb lights, you know you have tip/tip conductivity.


Checking speaker cabs for tip/positive polarity...

The cabs themselves can be checked using a 9v battery. Press the negative terminal of the battery against the sleeve of your 1/4 speaker cable connector (with the other end of the cable connected to your speaker cab), and touch the positive terminal of the battery against the 'tip' of the 1/4 inch connector, while you carefully watch the driver cones for movement. They should jump 'forward' or outward on all you cabs.

If you have a cab which sucks the speaker cones inward, during this test, then you have a reverse polarity cab which needs to be re-wired to function properly with other tip/positive cabs.

Both your cabs and cables must have tip/positive polarity, or you will experience phase issues and drastically reduced volume when using multiple cab setups.

As a side note...

It is also possible (but rare) for an amplifier to have mis-wired outputs. This can cause phase issues when using multiple cabs AND multiple amps, together.



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