Ohm reading error?

[Hunter Horton]

Hi I have 2 12"zv3s. They are dual 2 ohm subs wired to 2 ohm. At first they were reading 2.3 wired down which is normal however the other day I took out so I could put my amp rack and battery mount in and now they are reading 3.0. What is going on here? Thanks!

[reedal]

Measure each coil individually.

[Hunter Horton]

Measure each coil individually.

I did that when I first got them and out them in, they read right at the time. They are a pain in the ass to pull esp with the box they are current in. Could it be the ohm reader? as I used a buddies good one before and am using a 15 dollar cheapo but reads battery voltage and everything else correct. I was thinking that, but hope it's a last resort as they are a biach lol

[audiofanaticz]

If there is even a slight breeze in the air, its going to move the cone of the woofer causing a change in the reading on the multimeter.

If you try to check them after you been hammering on the subs for a while and they are hot, the heat will cause a higher resistance and be a change in the reading on the multimeter.

If you do not take care of your multimeter and just toss it around and are ruff with the leads/probes they will start to have more and more resistance causing a higher reading.

Make sure you touch the positive and negative probe together and read what number it says. it should say 0 or very close to 0 if your leads are good, if it says something like 0.9 then your leads are taking a crap so make sure you subtract whatever number is showing when you touch the probes together from the actual reading when you measure the voice coils.

So if your meter says 0.9ohms and your woofers say 2.9 ohms, subtract 0.9 from 2.9 and you have 2.0 ohms.

Also make sure your battery in the multimeter is good and not dead, that can cause false readings.

Lastly you can never compare a reading from a several hundred dollar name brand multimeter to something you bought at walmart or radioshack for $20 or less.

If your comparing results you need to keep as much of the test environment identical otherwise you get skewed results.

[Wicks]

The Nominal (rated) impedance of a speaker will always be a bit different then the actual measured DC resistance (DCR).

Just because a speaker is "rated" at 2 ohms doesn't mean it will read exactly 2ohms on an ohmmeter which reads strictly DC.

Negating the added probe resistance is also a big factor when you're measuring such low resistances, as mentioned above.

[reedal]

Measure each coil individually.

I did that when I first got them and out them in, they read right at the time. They are a pain in the ass to pull esp with the box they are current in. Could it be the ohm reader? as I used a buddies good one before and am using a 15 dollar cheapo but reads battery voltage and everything else correct. I was thinking that, but hope it's a last resort as they are a biach lol

I hear ya. But if your test leads for the ohmmeter/DMM are showing good when touched together, that's the next thing I would do. Pull the subs and check each coil individually.

[Hunter Horton]

Right on thank you guys, I will probably pull them and check today before our local show. They have been clipped, but hardly at all, just a soft clip as soon as the bass hits with certain edited music. Just a quick flash then back off though less than half a second. Appreciate it

[Stephen13]

Keep in mind that the measured DC resistance of a voice coil is NOT the same thing as impedance which is an AC measurement that changes with frequency.