How to Tell if an MTX Subwoofer Is Four or Eight Ohm?
- 1). Examine your MTX subwoofer's magnet for any stickers relating to the ohm rating. Your subwoofer's magnet location is a rounded shape, at the rear of the speaker and near the wiring terminals. If your subwoofer is mounted in an enclosure, use a screwdriver to remove the mounting screws located around the outside perimeter of the speaker. Pull the speaker and out of the enclosure to check the magnet for the ohm rating information.
- 2). Utilize a digital multimeter to determine your subwoofer's ohm rating. Disconnect any speaker leads from your subwoofer's terminal connections. Turn on your digital multimeter. Set the device to read DC ohms. Refer to your digital multimeter's documentation if you are unsure how to set the device to use this function.
- 3). Connect the corresponding positive and negative multimeter probes to the subwoofer wiring terminals. Check the reading on your digital multimeter to determine your subwoofer's ohm rating. Subwoofers that are rated at 8 ohms will have a reading between 5 and 6 ohms, while 4-ohm subwoofers will show a reading between 2.5 and 3 ohms.
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