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Discussion Starter #1
I've had a box with 2 crunch 12" subs, a RF punch 60ix amp and an MTX rtx01 xover for about 17 years now. It hasn't been hooked up for about 9 yrs or so. I paid someone to do the wiring and hooking everything up originally. I have an 05 Nissan altima with the factory bose system and I want to integrate my subs the 60ix and the xover into it. I know I can use a LOC and I bought the scoche one from walmart but after reading and seeing some reviews I trashed the thought of using it and decided that since my stock head unit is made by Clarion and there are full output feed wires, I'd just tap into them Like this guy did When I use my MM to check how many ohms my subs are, I get 6. I can only measure from the leads on the outside sub since the other one is sealed inside the box. I've never heard of getting 6. 1,2,4,8 yes but not 6! Is that right? If so, how can I bridge them into my amp for maximum output?

Thanks

cp
 

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depends on how they were wired and what the impedance of the subs is. you have to understand that the DC resistance of speakers is almost always lower than its AC impedance.

A 4ohm sub will commonly be 3.6-3.8 ohms DC. so if they were wired series for 8 ohms, it might be 6.5-7 ohms. only way to know for sure is to check to see how it is wired.
 

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depends on how they were wired and what the impedance of the subs is. you have to understand that the DC resistance of speakers is almost always lower than its AC impedance.

A 4ohm sub will commonly be 3.6-3.8 ohms DC. so if they were wired series for 8 ohms, it might be 6.5-7 ohms. only way to know for sure is to check to see how it is wired.
noone would wire subs in series for a punch 60:D

i bet one of the subs is blown, or you are just getting a false reading. Take the time to pull the subs out of the box and measure them.
 

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Discussion Starter #4
Thanks for the replies. I just realized something. I did the test with them wired together. I need to disconnect the wires coming out of the box and then I'll get accurate readings. The box was working great when I pulled it out of my CRX so, I doubt it's blown from sitting down in my basement for a decade or so :D
 

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Thanks for the replies. I just realized something. I did the test with them wired together. I need to disconnect the wires coming out of the box and then I'll get accurate readings. The box was working great when I pulled it out of my CRX so, I doubt it's blown from sitting down in my basement for a decade or so :D
if its a ported box...expect a nest of mice to be living in there:D:D
 

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Discussion Starter #6
Nope, it's a sealed box. The outside speaker was totally gone. I tested it with the audible tone for ohms with my meter and got nothing. The sub inside the box was audible and read 6.7 ohms. It's an 8 ohm speaker so something is wrong with it too. I also tested it with a 9v battery and that worked both ways. There is a small tear in the spider that I'm going to try to fix but otherwise it's intact. I'm planning on building a custom fiberglass box for it now. It only needs 1³ ft of airspace so it should fit nicely behind the wheel well. I'm going to mount the amp inside of the spare tire. Should be nice when all is said and done.
 

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Nope, it's a sealed box. The outside speaker was totally gone. I tested it with the audible tone for ohms with my meter and got nothing. The sub inside the box was audible and read 6.7 ohms. It's an 8 ohm speaker so something is wrong with it too. I also tested it with a 9v battery and that worked both ways. There is a small tear in the spider that I'm going to try to fix but otherwise it's intact. I'm planning on building a custom fiberglass box for it now. It only needs 1³ ft of airspace so it should fit nicely behind the wheel well. I'm going to mount the amp inside of the spare tire. Should be nice when all is said and done.
6.7 may be normal for an 8ohm driver.
 

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isobaric is fairly pointless these days anyway. With the low VAS subs available to us and cheap power. no need to take the 6db hit with isobaric.
 

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If the other sub is blown then that box is way too small for a single large box sub to be trying to push. Replace it with a new sealed box sub capable of pushing a small sealed enclosure. And realize that you might need to get a more powerful amplifier.
 

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Discussion Starter #11
This Crunch speaker is so old but I do recall it only needing 1³ ft of airspace. Am I wrong about that? I think the punch 60ix will provide enough power if I wire it right. These amps were very underrated. It's 260 watts max @ 4ohms and 120 rms @ 4ohms. I just want a little deeper bump than the factory bose subs can provide.
 
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