Sub is reading 2-ohm on DMM but it's suppose to be 4-ohm

[james33440 10+ year member]

I bought a setup off eBay for dirt cheap IMO.

It consists of a JL Audio 300/2 amp and a JL Audio 12W0. I assumed the sub was the 4-ohm version. Well I received the package today and it work but only one channel of the amp. I have to tap out the screw for the negative side to bridge the amp.

It really doesn't sound loud at all. I really can't tell it is on. Hopefully, because the amp is just playing on one channel. I hope this will all change once I bridge the amp.

Now, I assume this sub would be 4-ohm. However, I checked my amp and my sub and both are reading anywhere from 1.7-2.0 ohm. Is that right? It just doesn't sound right.

I haven't taken the sub out of the sealed box. However, once I get off work I will remove the sub to see what model it is for sure. As far as I know it's a SVC sub.

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[302yota 10+ year member]

if it is a svc 4ohm sub....and bridged across a 2-channel amp...it should drop the load down to 2ohms

 

[bonesninja 5,000+ posts]

I bought a setup off eBay for dirt cheap IMO.
It consists of a JL Audio 300/2 amp and a JL Audio 12W0. I assumed the sub was the 4-ohm version. Well I received the package today and it work but only one channel of the amp. I have to tap out the screw for the negative side to bridge the amp.

It really doesn't sound loud at all. I really can't tell it is on. Hopefully, because the amp is just playing on one channel. I hope this will all change once I bridge the amp.

Now, I assume this sub would be 4-ohm. However, I checked my amp and my sub and both are reading anywhere from 1.7-2.0 ohm. Is that right? It just doesn't sound right.

I haven't taken the sub out of the sealed box. However, once I get off work I will remove the sub to see what model it is for sure. As far as I know it's a SVC sub.

it is a single coil, they only came in 4 ohm, 8 ohm, or 12 ohm. But you are reading DC resistance with your dmm....the 4 ohm is nominal impedance. But 2 ohms is a bit low in my opinion

 

[avs20 10+ year member]

if it is a svc 4ohm sub....and bridged across a 2-channel amp...it should drop the load down to 2ohms

Bridging an amp doesnt change the impedance of a sub. It will still be a 4ohm sub one way or the other.

 

[302yota 10+ year member]

i thought he measured the load on the amp

 

[james33440 10+ year member]

it doesn't matter because it should still be the same load whether it's from the sub or the amp.

do you think the sub is bad?

 

[gunz4me 10+ year member]

Counterfeit 12w0?

 

[helotaxi 5,000+ posts]

Is the sub still wired to the amp? If the answer is "yes" you're measuring part of the amp when you're taking the measurement

 

[Horsemanwill 10+ year member]

if it is a svc 4ohm sub....and bridged across a 2-channel amp...it should drop the load down to 2ohms

please explain to me how that works?//content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

 

[gunz4me 10+ year member]

It really doesn't sound loud at all. I really can't tell it is on.

Welcome to my world. I could not stand the lack of sub bass output from a pair of 10w3v2s because their only audible range was from 50 to 80 hz in a .75 cubic foot sealed enclosure (ETA Per sub). I am going to try them ported next because I had yet another buyer back out on them. If I don't like them ported, they are going out by the curb and I am sure they will take care of themselves once I leave them there!

Hopefully, because the amp is just playing on one channel. I hope this will all change once I bridge the amp.

I wouldn't hold my breath. Doubling the power may not necessarily get you the level you were hoping for.

 

[shaneb 10+ year member]

This doesn't make sense.

If you put a 4 ohm speaker on an amp thats say...500rms @ 2 ohms bridged. (for talking purposes) the power will be cut in half due to added resistance with most amps...

 

[gunz4me 10+ year member]

The JL Audio 300/2 is rated to do 150 watts x 2 or 300x1 @ 4 ohms.

ETA: The op's sub is only getting 150 watts off of one channel right now, and when he bridges the amp, it should be getting 300.

 

[james33440 10+ year member]

Well I got some news.... I finally decided to just take the sub out and figure out what model it actually is. Remember, I bought this setup on eBay for $150. It was for a JL Audio 300/2 and a 12W0-4. However, I noticed that the sub didn't have a round cone, but it was flat. So I didn't really believe that it was a W0.

Anyway, when I took the sub out the first thing I noticed was that there were 2 VC's! I flipped over the sub and I just happened to receive a JL Audio 12W3V2-2. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

It turns out, the reason I was only getting a 2-ohm load was because they only had one VC wired up. ????

I checked both VC's and they both read about 2.3-2.5 ohm. I rewired the sub and now the final load is 4-ohm.

I will install it tomorrow and see how the 4-ohm load sounds bridged on the 300/2.

Now, I am thinking of put this amp on eBay and getting a 500/1 amp. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[groundpound4200 5,000+ posts]

Welcome to my world. I could not stand the lack of sub bass output from a pair of 10w3v2s because their only audible range was from 50 to 80 hz in a .75 cubic foot sealed enclosure (ETA Per sub). I am going to try them ported next because I had yet another buyer back out on them. If I don't like them ported, they are going out by the curb and I am sure they will take care of themselves once I leave them there! QUOTE]
Huh? my w3s got nice and low sealed and ported. Let me know when they hit the curb. I will be there to pick them up.//content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[gunz4me 10+ year member]

Huh? my w3s got nice and low sealed and ported. Let me know when they hit the curb. I will be there to pick them up.//content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

Lucky you. I think I had great expectations after hearing how God-like these subs were from the local fanboys. After getting them, and sticking anywhere between 500 and 1,000 watts RMS to the pair in this double .75 cubic foot sealed box, I was totally let down!

They have great SQ, but I am lacking something that I KNOW is supposed to be there musically and these 10w3v2s just don't reproduce anything in the 30 to 40 hertz range! It really sucks when you are listening to a drum and bass track and you don't hear those low notes that you are expecting to hear!

Regardless, I have a very bad feeling that I am just going to destroy these subs if they sound like shite in a ported box because of they headache they have managed to cause me!//content.invisioncic.com/y282845/emoticons/verymad.gif.3f39c5c2fd57527b671fad3efdfac756.gif