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how do you figure out box rise?


noobslayer77

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so maybe anyone want to actually help. I'm trying to learn, that's the point of this forum. That condescending response did nothing. No shit i'm in over my head, that's why i'm asking these questions. What tools are necessary to figure out box rise? Is a signal generator the only way that you can do it? Would you be able to do it by running sine sweeps or test tones and hooking a dmm up to your amp output wires and check the ohms?

Signal generator and DMM is what we used 20 years ago. The correct tool for doing impedance sweeps is Dayton WT3 (old version) or DATS. It also quickly calculates TS parameters of raw drivers.

I think the reason people are picking apart the question is why do you think you need to see your impedance curve?

IMsg can do that. And a few dozen other tests/procedures/wants. Ts, parameters, help with volume, area, ported, and sealed (band pass 4th orders, and 6th orders.. front and rear chambers)

Ill take this over that Wt3 for days and days and days and days.

But, i see you at least understand where I WAS coming from. That said, jump into 2005 and play with a IMsg dude. Really.

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Take your reactive impedance and subtract your nominal impedance from it and that is your box rise. Your nominal impedance is the load at the amp, for example let's say 1 ohm. You will need a clamp meter and a dmm to read voltage and amperage from the amp on a burp. So I will throw some hypothetical numbers out there to show how it is done.

Let's say your amp is wired to 1 ohm nominal and on a 50hz burp you produce 117.6 volts and 42.4 amps. To find out what you are working with you will need to take 117.6 and divide it by 42.4, which will give you 2.77 ohms. The 2.77 ohms will be your reactive impedance. Next you will take 2.77 and subtract 1 ohm from it. This gives you 1.77 ohms, this is how much box rise you will have. This is the method that on how to do so explained to me by Mike Singer about 6 years ago and is how he told me he figured out box rise in his vehicle. If I'm not mistaken he was told this information from Team Neo Eric, so this is not my info as I will give them credit for showing me how to do so.

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Box rise is a mythical creature that is summoned by the bass freq from a beginners stereo system. It is combated by bolting your stereo system down really good and getting an smd decal.

In the real world though its considered life. Because music is reactive and your impedance will never stay the same. It jumps around like a bitch. Put a dmm on your sub and push the cone. Watch the impedance change. Now fix that... Wait you can't...

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Why exactly are you worried about in the first place? Unless your chasing db's who cares.

That being said a lot of people's definition of "music" is a clipped 30 hz sine wave with some 80 IQ knuckle head grunting about committing crimes and his genitals.

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Instead of worrying about rise. Find your peaks. That will help you way more.

And yes there there are several tools for that also.

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I was just curious. I'm not worried about competing. I was just interested to see how much different frequencies varied the impedance. I just wanted to know a little bit more. Sorry for not spending hours reading through stuff on the internet. I figured i could just ask on here and someone would simply answer. I also apologize for not knowing that using a ported box and a sealed box was a horrible idea. It seemed like an easy way to add another sub without building a new box or taking out my back seats.

Take your reactive impedance and subtract your nominal impedance from it and that is your box rise. Your nominal impedance is the load at the amp, for example let's say 1 ohm. You will need a clamp meter and a dmm to read voltage and amperage from the amp on a burp. So I will throw some hypothetical numbers out there to show how it is done.

Let's say your amp is wired to 1 ohm nominal and on a 50hz burp you produce 117.6 volts and 42.4 amps. To find out what you are working with you will need to take 117.6 and divide it by 42.4, which will give you 2.77 ohms. The 2.77 ohms will be your reactive impedance. Next you will take 2.77 and subtract 1 ohm from it. This gives you 1.77 ohms, this is how much box rise you will have. This is the method that on how to do so explained to me by Mike Singer about 6 years ago and is how he told me he figured out box rise in his vehicle. If I'm not mistaken he was told this information from Team Neo Eric, so this is not my info as I will give them credit for showing me how to do so.

^^ thank you that was helpful

As far as condescending (this is how its spelled). You didn't need to say, " you're obviously in over your head." a simple ,"you probably don't need to worry about this unless you are competing or trying to gain a decibel or so." would have done just fine.

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I was just curious. I'm not worried about competing. I was just interested to see how much different frequencies varied the impedance. I just wanted to know a little bit more. Sorry for not spending hours reading through stuff on the internet. I figured i could just ask on here and someone would simply answer. I also apologize for not knowing that using a ported box and a sealed box was a horrible idea. It seemed like an easy way to add another sub without building a new box or taking out my back seats.

Take your reactive impedance and subtract your nominal impedance from it and that is your box rise. Your nominal impedance is the load at the amp, for example let's say 1 ohm. You will need a clamp meter and a dmm to read voltage and amperage from the amp on a burp. So I will throw some hypothetical numbers out there to show how it is done.

Let's say your amp is wired to 1 ohm nominal and on a 50hz burp you produce 117.6 volts and 42.4 amps. To find out what you are working with you will need to take 117.6 and divide it by 42.4, which will give you 2.77 ohms. The 2.77 ohms will be your reactive impedance. Next you will take 2.77 and subtract 1 ohm from it. This gives you 1.77 ohms, this is how much box rise you will have. This is the method that on how to do so explained to me by Mike Singer about 6 years ago and is how he told me he figured out box rise in his vehicle. If I'm not mistaken he was told this information from Team Neo Eric, so this is not my info as I will give them credit for showing me how to do so.

^^ thank you that was helpful

As far as condescending (this is how its spelled). You didn't need to say, " you're obviously in over your head." a simple ,"you probably don't need to worry about this unless you are competing or trying to gain a decibel or so." would have done just fine.

Dude, I feel your pain completely. I've been here since the beginning and you want some advice? More than half of the people on here are assholes and are quick to pick you apart. You would think they would understand that this is a forum. I have included the definition below for those who may not understand. The way I deal with them now is just don't respond to them. Just act like they didn't post at all and they eventually stop.

Anyways, looks like Nightshade was kind enough to help ya out so there you go.

fo·rum

noun \ˈfr-əm\

: a meeting at which a subject can be discussed

: a place or opportunity for discussing a subject

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I was just curious. I'm not worried about competing. I was just interested to see how much different frequencies varied the impedance. I just wanted to know a little bit more. Sorry for not spending hours reading through stuff on the internet. I figured i could just ask on here and someone would simply answer. I also apologize for not knowing that using a ported box and a sealed box was a horrible idea. It seemed like an easy way to add another sub without building a new box or taking out my back seats.

Take your reactive impedance and subtract your nominal impedance from it and that is your box rise. Your nominal impedance is the load at the amp, for example let's say 1 ohm. You will need a clamp meter and a dmm to read voltage and amperage from the amp on a burp. So I will throw some hypothetical numbers out there to show how it is done.

Let's say your amp is wired to 1 ohm nominal and on a 50hz burp you produce 117.6 volts and 42.4 amps. To find out what you are working with you will need to take 117.6 and divide it by 42.4, which will give you 2.77 ohms. The 2.77 ohms will be your reactive impedance. Next you will take 2.77 and subtract 1 ohm from it. This gives you 1.77 ohms, this is how much box rise you will have. This is the method that on how to do so explained to me by Mike Singer about 6 years ago and is how he told me he figured out box rise in his vehicle. If I'm not mistaken he was told this information from Team Neo Eric, so this is not my info as I will give them credit for showing me how to do so.

^^ thank you that was helpful

As far as condescending (this is how its spelled). You didn't need to say, " you're obviously in over your head." a simple ,"you probably don't need to worry about this unless you are competing or trying to gain a decibel or so." would have done just fine.

Dude, I feel your pain completely. I've been here since the beginning and you want some advice? More than half of the people on here are assholes and are quick to pick you apart. You would think they would understand that this is a forum. I have included the definition below for those who may not understand. The way I deal with them now is just don't respond to them. Just act like they didn't post at all and they eventually stop.

Anyways, looks like Nightshade was kind enough to help ya out so there you go.

fo·rum

noun \ˈfr-əm\

: a meeting at which a subject can be discussed

: a place or opportunity for discussing a subject

Its not that anyone on here is an ass or trying to pick you apart. Its that your to lazy to do research and testing. Its not our fault you copied your friends school work instead of doing your own. Maybe if you would have paid attention you would have realized school wasn't only teaching you what was on the book but also to be independent rather then wanting answers handed to you.

t1500bdcp

2 t2d4 15"

1 t600.4

1 t400.2

1 set p1 tweets

singer alt, tons of wiring, smd vm-1, 80prs, back seat delete, still in the works, aiming for a 145-147 with the ability to play 25hz up to 50hz.

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