i've been wanting to test that my sub is not blown. i purchased an anolog multimeter at radio shack to do this. i followed some instructions that i found online. according to what i read, when i attach the probes to the speaker terminals i should get a rating close somewhere between 3.4 to 4.4 ohms since i have a dual 4ohm sub. however, the gauge keeps going all the way to zero and doesn't move from there. i did calibrate the gauge first by touching both probes together and setting the dial at "0". any ideas on what this means?

 

The DC resistance and the AC impedance are two totally different things.

Subs have rather massive, large-gauge voice coils that will typically read VERY close to ZERO resistance on the average ohmmeter.

Actually determining the impedance of a speaker is quite beyond a simple Radio Shack multimeter.

If your sub's voice coil reads close to "0" ohms, and if the speaker makes a 'click' or 'thump' sound if you tap the terminals from a 9 volt battery to the sub's terminals, you are as "OK" as you can check with simple tests and tools.

Good luck!

Tomas

 

first make sure your ohm meter works by testing a resistor, but since you said you just bought the meter im assuming it works, so yes your sub is blown

 

i think the problem might be the meter i'm using. the only impedance setting is has is labeled as RX 1K and the upside down U ohm symbol. pardon my ignorance, but does this mean the reading will only be in increments of a thousand? if that's the case i can see why it is only reading "0".

 

yea your measuring a 4 ohm sub so if your setting is on 1000 then it will read 0

 

fujitech43, i guess i should have paid more attention to the meter before buying it.

Tomas, i found a 9V battery and did what you suggested. the speaker indeed makes a click sound and the cone moves up and down. seems like it is okay after all. if there was something wrong with the speaker, what would happen when attaching a battery? no click or movement at all? thank you for your help!

 

<=== Listen to the electrical engineer...

Yeah, if it didn't click, thump, or move, it would be an indication that it was likely toast. Since it DOES react, it is doing what it should.

That doesn't mean it is perfect, but it does mean it should product sound if the amp is feeding it a decent signal.

If it doesn't work when connected to the amp, check the amp.


Tomas

 

*listening*

the amp was never an issue, i just wasn't sure if the buzz/rattle was coming from the speaker or the enclosure. the bass would still hit hard with the same intensity, so i didn't know what to think.

it turns out the enclosure is all cracked up so i'm positive that's what is making the noise. plus, i played the sub out of the enclosure and it moved up and down fine.

 

Glad you seem to have found your problem.

If the enclosure is not solid, that is your most likely problem.

Take care,
Tom

 

I had that problem with my sub in my fiberglass enclosure. it wasn't air tight, so i ended up having a ton of weird sounds coming from it.

 

well, i'm realizing that the bazooka enclosure is not the best built enclosure out there. i'm going to try one of those fiberglass repair kits and give it another layer or two of reinforcement. this will be my first time dealing with fiberglass so wish me luck!