Impedance rise Question

[Purplehaze]

Not sure about your main question, but I did just build a new box, and I noticed a difference from regular mounting to inverted. 3 -12's wired @1.34ohm regular mount had a rise to 2.8ohm and inverted show almost none @1.4ohm. All readings are w/o power. I think the difference is in the terminals not being there inverted, maybe?

Not sure if this helps, or is common knowledge, just thought I'd share

[Punkeyboozter]

Good question I'm along for the lesson.

x2

I'm wanting to know the same.

I've read people saying smaller boxes equal less rise but at the same time, people say larger box equals less rise...

And I'm like WTf?

And I'm sorry to threadjack, but could running speaker wires directly from sub to amp and nothing in between lower rise?

I always rise to the occasion

[audiofanaticz]

What dc hoe said.

1 big amp, or 2 little amps (strapped or ran independently).

Either way the same woofers in the same box, in the same vehicle will have the same impedance rise, even if you wire it to .25ohms, your actually rise will be the same, but just different numbers.

So if you wire 2 dual 1ohm woofers and wire them to 1 ohm, and rise to 4 ohm

or

if you take your 2 dual 1 ohm woofers and wire them to .25 ohms and rise to 3.25 ohms.

Your actual impedance rise is still going to be 3 ohms.

kinda late, and tired so hopefully I worded this to make sense. lmao

[audiofanaticz]

Not sure about your main question, but I did just build a new box, and I noticed a difference from regular mounting to inverted. 3 -12's wired @1.34ohm regular mount had a rise to 2.8ohm and inverted show almost none @1.4ohm. All readings are w/o power. I think the difference is in the terminals not being there inverted, maybe?

Not sure if this helps, or is common knowledge, just thought I'd share

has nothing to do with it..

You can not calculate impedance rise unless you are playing a tone, have a digital multimeter, and a clamp meter. All you are knowing is the DCR of all the coils wired together (either in series, parallel, or series/parallel, depending on your needed wiring to achieve the impedance you are after.

All you are doing is checking the DCR of the woofers (which is the impedance of a coil or multiple coils wired together in series or parallel).

Your DCR should read the same at all times (unless your voice coil is very hot, your woofer is blown, or the cone is being pressed).

So when you test your coil with your multimeter, if your impedance reads 1ohm without it in a box, it should read 1ohm when its in a box, or 1ohm when its inverted (this is just a single sub example of coarse, since like i said the dcr will change when wiring more than 1 sub together).

Box size alone (no matter how big, or how small) will never change the dcr or impedance of a voice coil(s).

If you inverted your woofer and your impedance has changed you are doing 1 of 2 things.

1- you wired your woofers differently.

2- when you inverted your woofers, your cutout hole is not large enough and is pushing on the surround which means the cone is moved and effecting the reading on the multimeter. Also if this is the case, you will soon wear a hole through your surround!!!!!!!

[Purplehaze]

Not sure about your main question, but I did just build a new box, and I noticed a difference from regular mounting to inverted. 3 -12's wired @1.34ohm regular mount had a rise to 2.8ohm and inverted show almost none @1.4ohm. All readings are w/o power. I think the difference is in the terminals not being there inverted, maybe?

Not sure if this helps, or is common knowledge, just thought I'd share

has nothing to do with it..

You can not calculate impedance rise unless you are playing a tone, have a digital multimeter, and a clamp meter. All you are knowing is the DCR of all the coils wired together (either in series, parallel, or series/parallel, depending on your needed wiring to achieve the impedance you are after.

All you are doing is checking the DCR of the woofers (which is the impedance of a coil or multiple coils wired together in series or parallel).

Your DCR should read the same at all times (unless your voice coil is very hot, your woofer is blown, or the cone is being pressed).

So when you test your coil with your multimeter, if your impedance reads 1ohm without it in a box, it should read 1ohm when its in a box, or 1ohm when its inverted (this is just a single sub example of coarse, since like i said the dcr will change when wiring more than 1 sub together).

Box size alone (no matter how big, or how small) will never change the dcr or impedance of a voice coil(s).

If you inverted your woofer and your impedance has changed you are doing 1 of 2 things.

1- you wired your woofers differently.

2- when you inverted your woofers, your cutout hole is not large enough and is pushing on the surround which means the cone is moved and effecting the reading on the multimeter. Also if this is the case, you will soon wear a hole through your surround!!!!!!!

Thanks for the explanation, but I took lots of pics, and I am pretty sure they were wired the same. Only difference is that when regular mounted, the circuit had to go through two bolts, with washers and nuts, and now they have wire directly from the amp to the subs terminals.

But I understand what your saying, that's how I thought it was, but when I put the meter on it and got those reading I was confused. You are probably right, I probably had them wired different and just didn't know it.

And it couldn't have changed from the surround rubbing, they are not touching, or laying against the cutout, and at the time I took the reading the subs had not been played yet. And I checked it when I installed them, it looked like it would clear, but since you mentioned it, better safe than sorry!

I'd say I got it right now, and it was just off before

[kirill007]

smaller box and more port is less rise.

That's how easy it is.

[Team Sundown's Charles]

What dc hoe said.

1 big amp, or 2 little amps (strapped or ran independently).

Either way the same woofers in the same box, in the same vehicle will have the same impedance rise, even if you wire it to .25ohms, your actually rise will be the same, but just different numbers.

So if you wire 2 dual 1ohm woofers and wire them to 1 ohm, and rise to 4 ohm

or

if you take your 2 dual 1 ohm woofers and wire them to .25 ohms and rise to 3.25 ohms.

Your actual impedance rise is still going to be 3 ohms.

kinda late, and tired so hopefully I worded this to make sense. lmao

Makes sense.

Does 2 amp divide the rise? So if my rise 3 ohms with 1 amp does this mean that if i go to 2 amps both amps will see rise of 3 ohms or would each see a rise of 1.5? If that makes sense.

[AA98hoe]

Yes sir.... are you running amps strapped or unstrapped? And what is your actual rise.. numbers box specs etc? On my 4 -18s box I'm running it on the small side so its more of a spl box.. does big numbers.. try adding bricks inside your box to take up displacement and see what it does.. that's a easy removable test

[PUNKYOU007]

Rise is a bitch, trust me I am being robbed of gobs of power due to how high mine is...what I have learned is to just not worry about rise. You want more power to your subs get more power or up your voltage (assuming your electrical can take it). Or rebuild and try again, but its not something you can plan for so expect to do lots of rebuilding if it bothers you that much.

[Team Sundown's Charles]

Well my plan is to run the amps straped @ 1ohm (ea amp @ .05)It doesn't bother me. But what i'm doing is rebuilding my setup and i wanted to atless keep it down. Because I want to run a low watt class. So I want to get as much power as possible to the subs and stay in my 2500 watts class. Just trying to see if amps play apart in it.