detecting a rise in impendance

[.::DuD3::. 10+ year member]

is there anyway to detect a rise in impendance? i want to say the dmm will tell you, but i dont own one so i dont know. and is there any way to help prevent it? i know heat and enclosure design are factors, but how would you solve these problems per se?

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[jeepintn 10+ year member]

from what i understand, when a sub gets power its coils heat up, therefor cooling may help ? ? im not sure, just a thought

 

[Twistid 5,000+ posts]

from what i understand, when a sub gets power its coils heat up, therefor cooling may help ? ? im not sure, just a thought

pour water in the port of the box to help the coils keep cool //content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif

 

[.::DuD3::. 10+ year member]

like i know the box design plays a role, but how would you fix something like that? rounded corners inside the box or something? //content.invisioncic.com/y282845/emoticons/confused.gif.e820e0216602db4765798ac39d28caa9.gif

 

[.::DuD3::. 10+ year member]

pour water in the port of the box to help the coils keep cool //content.invisioncic.com/y282845/emoticons/naughty.gif.94359f346c0f1259df8038d60b41863e.gif

BRB ... //content.invisioncic.com/y282845/emoticons/laugh.gif.48439b2acf2cfca21620f01e7f77d1e4.gif

 

[Chevyaudio 5,000+ posts]

To graph impedance rise. you need a True RMS DMM and a Clamp meter...To lower your rise, You need to be dammn proficient at building boxes...and Build and test and build and test. Not and easy process

 

[.::DuD3::. 10+ year member]

To graph impedance rise. you need a True RMS DMM and a Clamp meter...To lower your rise, You need to be dammn proficient at building boxes...and Build and test and build and test. Not and easy process

ok cool, so is there a set of "rules" that box builders go by to prevent it? im just curious because if i build my box in the future i dont want to contribute to the problem even more.

 

[Immacomputer 10+ year member]

You cannot avoid impedance rise because there is going to be inductance when you put a sub in an enclosure. Even when you put power to a sub free-air, there is going to be a rise in impedance at Fs.

With enclosures though, you can change the design to change where the impedance spikes but you cannot avoid it. It really isn't a big deal and not something you need to worry about. At the point where there is a spike, the system will be very efficient anyways. Just because there will be less power delivered and used by the sub does not mean it will be noticeably quieter at this point. I think you're stuck on the "you need power to get loud" idea that many people get caught up on.

 

[.::DuD3::. 10+ year member]

You cannot avoid impedance rise because there is going to be inductance when you put a sub in an enclosure. Even when you put power to a sub free-air, there is going to be a rise in impedance at Fs.
With enclosures though, you can change the design to change where the impedance spikes but you cannot avoid it. It really isn't a big deal and not something you need to worry about. At the point where there is a spike, the system will be very efficient anyways. Just because there will be less power delivered and used by the sub does not mean it will be noticeably quieter at this point. I think you're stuck on the "you need power to get loud" idea that many people get caught up on.

no i was just curious if theres anyway you can try and help reduce it. if i could help reduce the affects of it, i thought i could just get more out of the woofer. if theres nothing i can really do about it, then i wont worry about it.

 

[kicker06 10+ year member]

Impendence Rise differs on different Frequencies. So with music it's all over the place.

Coooorrect?

 

[Immacomputer 10+ year member]

Impendence Rise differs on different Frequencies. So with music it's all over the place.
Coooorrect?

The impedance varies over frequencies but the peak of the spike mainly varies with heat.

no i was just curious if theres anyway you can try and help reduce it. if i could help reduce the affects of it, i thought i could just get more out of the woofer. if theres nothing i can really do about it, then i wont worry about it.

It is possible to reduce it, but I'm not going to say how because it is not safe nor would it help anything. You're also not going to really lose anything with a spike. Like I said before, the system will be very efficient at the point of a spike and the power you're not getting doesn't really matter. Every sub/enclosure setup has spikes but they really are not something you need to worry about.