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Discussion Starter #1
I have been interested in buying some subwoofers on CL and they don't have a box. How should I go about testing them? Can I just move the sub up and down and listen for scratching sounds or would it be better to hook it up without it being in a box at all? He said he has an amp with a subwoofer that I can test them with. Will that be enough or do they really need to be in a box?

Thanks
justind
 

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I think if you just hook it up to an amp and make sure that they move and respond to power, you should be fine. As far as how they sound, I think you would need a box that's the correct size to make that decision.

If they are the brand that you want, you've done your research and the move when powered by an amp, then you should be in the clear.

That's exactly how I bought my recent pair of JL 12W3V3's. I haven't regretted it for a second (but at $150 for the pair, it's tough to be upset).

Hope this helps.
 

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Discussion Starter #3
okay thanks for the info. I will have him hook them up. I am just worried about the VC being bad or something. Anyone else? I'm not worried about how they sound, just concerned if they are in proper working order. Will I need a box for that?

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Justind
 

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I use a multimeter to measure resistance on the subwoofer. If one coil doesn't match the other by more than .1 ohm, walk away. I also hook up subs to an amp freeair. I beat on my $40 Brahma 12 freeair with a proaudio amp attached. It moved a TON, and made no bad noises. Seems like a good sub to me!

Eric
 

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Discussion Starter #5
I use a multimeter to measure resistance on the subwoofer. If one coil doesn't match the other by more than .1 ohm, walk away. I also hook up subs to an amp freeair. I beat on my $40 Brahma 12 freeair with a proaudio amp attached. It moved a TON, and made no bad noises. Seems like a good sub to me!

Eric
Okay. Someone had mentioned that same thing. So your saying that they shouldn't be more then .1 ohm away from each other, and not the rated 4 ohms they are? I know that sometimes when a subwoofer is rated for 4ohms that it can actually be a little off of that rating.

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Justind
 

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My Brahma 12 is a dual 2 ohm sub. Both coils measure 1.6 ohms. If one was 1.6 and the other was higher than 1.7 or lower than 1.5, I wouldn't buy it.

If you're buying a single voice coil sub, that logic doesn't work, but if you look at the T/S specs for the woofer, you should see "Re" xx ohms. If its 4 ohm, generally, you'll see around 3.2 ohms, etc. Look up the sub you're gonna check out, and you'll know. If it varies from that, don't buy it.

Also, you can GENTLY push the subwoofer straight inward to see if it makes any scraping noises, as this is a very bad sign as well.

Eric
 

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Discussion Starter #7
My Brahma 12 is a dual 2 ohm sub. Both coils measure 1.6 ohms. If one was 1.6 and the other was higher than 1.7 or lower than 1.5, I wouldn't buy it.

If you're buying a single voice coil sub, that logic doesn't work, but if you look at the T/S specs for the woofer, you should see "Re" xx ohms. If its 4 ohm, generally, you'll see around 3.2 ohms, etc. Look up the sub you're gonna check out, and you'll know. If it varies from that, don't buy it.

Also, you can GENTLY push the subwoofer straight inward to see if it makes any scraping noises, as this is a very bad sign as well.

Eric
Thanks Eric for the info. They both are single 4 ohm speakers. I looked at the "Re" spec and it said 3.1 ohm so I'll be looking for that number on my meter.

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Justind
 

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I'll dispute that comment. I bought my Brahma 'blown' for cheap enough, that I knew I could have it reconed and STILL be way under the new price. I had $70 in it, and a recone was ~$100...still about $100 off the new price.

Only other money I've got in it, is a set of terminals that are binding post to replace the cracked stock ones that I didn't care for anyway.

Eric :D
 
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