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IAD-Zak
09-12-2012, 12:41 AM
so my buddy says that the smaller the box the less the rise and the larger the more rise.. is this true?

kushy_dreams
09-12-2012, 12:19 PM
people always argue this and there never has been a clear answer

Flex68
09-12-2012, 12:24 PM
so my buddy says


Kinda reminds me of a redneck's last words: "Hey, watch this"

BassMechkanic
10-15-2012, 10:09 AM
yes and no......... each box different, infact i have seen same air space and port, but postion of sub in box made difference........ like to try diflection panel behind sub to see if it affects it

JoeK
10-15-2012, 07:23 PM
My 3.2cu box rises to 3.1 @ 50hz whereas my friends box @ 4.5cuft only rises to 2.2 (both wired down to .7), but box rise is irrelevant seeing as impedence is always changing

mat3833
10-15-2012, 10:06 PM
ok, i feel REALLY stupid. but wtf is box rise?

Matt

n8skow
10-16-2012, 10:55 AM
When your bass is slapping so hard your enclosure levitates...
=P



ok, i feel REALLY stupid. but wtf is box rise?

Matt

n8skow
10-16-2012, 11:21 AM
With a sealed enclosure, as you approach a free-air environment (larger box) the impedance will increase.
With a ported enclosure, you are also introducing a pronounced dip (at tuning) with a peak a bit above tuning.

Many outside factors can also affect impedance (such as temperature, number of coils, etc.) - but understand that impedance rise is only a 'bad' thing from the amp's perspective - as it will put out less power - but the highest efficiency of the system will be around the same point as the highest impedance.

mat3833
10-16-2012, 12:44 PM
oh! ok, never heard it called box rise. with Tapped Horns when u use multiple drivers in a single horn you can get multiple impedance peaks/ more overall efficency.

Matt

LBC
10-16-2012, 12:55 PM
Impedence rise varies with frequency. At some freqs it actually drops. The reason we call it "impedence rise" is because we only measure it for SPL burps and only at our burp frequency. It means absolutely nothing for most of you on this site who play music through your stereo. It will cause you to damage your equipment.
Impedence rise does not have a predictable pattern or formula to calculate it because as stated, there are quite a few things that can manipulate it.

n8skow
10-16-2012, 01:02 PM
Impedance 'can' be plotted to a reasonable degree (though agreeable, real-life vs. computer simulation leaves some discrepancies)



Impedence rise varies with frequency. At some freqs it actually drops. The reason we call it "impedence rise" is because we only measure it for SPL burps and only at our burp frequency. It means absolutely nothing for most of you on this site who play music through your stereo. It will cause you to damage your equipment.
Impedence rise does not have a predictable pattern or formula to calculate it because as stated, there are quite a few things that can manipulate it.

LBC
10-16-2012, 01:06 PM
Impedance 'can' be plotted to a reasonable degree (though agreeable, real-life vs. computer simulation leaves some discrepancies)

Lol. I know that there are programs that show a projected impedence curve. Compare that after clamping each freq and you'll understand just how wrong you are good sir.

n8skow
10-16-2012, 02:27 PM
...the projected-versus-real impedance 'values' may be a bit off, sure (and I don't know of any software that takes speaker fatigue, power and/or port compression, etc., and the resulting changes in the T/S parameters into account) but the 'shape' of the curve will be fairly reliable.

If perhaps you are referring to how putting the 'projected' system into a closed, reflective environment (the car) is going to influence this, then I would agree. Calculating the implications of cabin gain are going to be quite messy...

Your comment stops just short of throwing the baby out with the bathwater though.
=)


Lol. I know that there are programs that show a projected impedence curve. Compare that after clamping each freq and you'll understand just how wrong you are good sir.

LBC
10-16-2012, 02:46 PM
...the projected-versus-real impedance 'values' may be a bit off, sure (and I don't know of any software that takes speaker fatigue, power and/or port compression, etc., and the resulting changes in the T/S parameters into account) but the 'shape' of the curve will be fairly reliable.

If perhaps you are referring to how putting the 'projected' system into a closed, reflective environment (the car) is going to influence this, then I would agree. Calculating the implications of cabin gain are going to be quite messy...

Your comment stops just short of throwing the baby out with the bathwater though.
=)

We are both saying things we aren't going to prove. I made a statement I know to be true through my many SPL builds and testing. You made a statement based on a graph you saw in some software. Then you went on to admit that the graph is worthless when you actually go to USE your woofer and enclosure and tried to mock me for being accurate and telling the truth. You must be a democrat. With what I've seen so far, a discussion would be fruitless.

n8skow
10-16-2012, 03:46 PM
On the contrary...
I'm not sure I've saved my past graphs here, but I'll fire up WinISD and my DATS this evening, if that's what your wanting to see...

Software is NOT worthless - (your putting words in my mouth).
I've asserted that a software plot is quite helpful, and stand by that. You obviously have your own methods for planning a woofer enclosure, and that's fine, but I thought we were having a civilized conversation here.

You have the scorn in your voice of someone that's spent countless hours planning something out, and been disappointed with the actual result (such is the life of SPL'er - I know...), but I believe you are referring to conditions way outside the scope of the original question.

P.s. I consider myself political affiliation Independent - will have to save your Obama hatin' for another thread. =)


We are both saying things we aren't going to prove. I made a statement I know to be true through my many SPL builds and testing. You made a statement based on a graph you saw in some software. Then you went on to admit that the graph is worthless when you actually go to USE your woofer and enclosure and tried to mock me for being accurate and telling the truth. You must be a democrat. With what I've seen so far, a discussion would be fruitless.

LBC
10-16-2012, 08:41 PM
On the contrary...
I'm not sure I've saved my past graphs here, but I'll fire up WinISD and my DATS this evening, if that's what your wanting to see...

Software is NOT worthless - (your putting words in my mouth).
I've asserted that a software plot is quite helpful, and stand by that. You obviously have your own methods for planning a woofer enclosure, and that's fine, but I thought we were having a civilized conversation here.

You have the scorn in your voice of someone that's spent countless hours planning something out, and been disappointed with the actual result (such is the life of SPL'er - I know...), but I believe you are referring to conditions way outside the scope of the original question.

P.s. I consider myself political affiliation Independent - will have to save your Obama hatin' for another thread. =)

Posting graphs is only half of the battle. I too can produce WINISD graphs. What I'm not willing to do is go clamp my woofers at all frequencies just to prove you wrong. You're not going to do it either, so it's not to the contrary. Again, what I'm saying is undisputably true yet you're attempting to skew the facts. The software itself is not worthless. The impedence plot IS worthless. In a real-world scenario (as you have admitted) that graph won't represent the REAL impedence plot. You've already admitted it, and you're continuing to argue. I don't really care what the readers of this thread or forum members think about me. We have both proved me correct. i will no longer be responding because any further discussion is as worthless as your impedence plot.

n8skow
10-17-2012, 12:44 AM
The only thing you've proven is that you have a somewhat short temper, and don't like being disagreed with (in which case the interwebs is gonna be a harsh ride for you, my friend).

Clamping woofers at all frequencies - indeed - that takes some time, and I'm sure you've got other things to do - (besides following up with supporting data)... good thing I picked up a DATS, takes it about 10 seconds... :graduate:

For everyone else - here's a couple graphs I grabbed this evening (please forgive the scale between the two being a tad off):

Daily beater box, Impedance plotted in WinISD
http://farm9.staticflickr.com/8046/8095907811_97f30bb275_z.jpg
WinISD is showing a predicted port tuning around the 34hz area (the lowest impedance dip to the right of the peak on the left) with impedance maxing out around the 58hz area

And here's what the DATS actually sampled in the car - (*a few words about that below the graph)
http://farm9.staticflickr.com/8191/8095914670_2ae88dbfc7_b.jpg
DATS is showing a similar shaped curve with tuning in the low 30s, and a shift to the left for the upper impedance peak. Why is this? Cabin gain (aka transfer function), as previously mentioned. Different vehicles are going to accentuate/attenuate different frequencies - and thus affect the impedance of the system.

*concerning my note above, this enclosure weighs around 150 pounds, not going to be able to get a out-of-car measurement at the moment. However, based on my experience, the impedance is going to raise slightly, and the peaks shift to that matching more closely the predicted WinISD curve.

So to sum up, top graph - took about 5 minutes of work at the keyboard.
Bottom graph - took about 3.5 hours of box building.
Now is that top graph 'close enough' for planning a box design? I suppose everyone has to decide that for themselves...



Posting graphs is only half of the battle. I too can produce WINISD graphs. What I'm not willing to do is go clamp my woofers at all frequencies just to prove you wrong. You're not going to do it either, so it's not to the contrary. Again, what I'm saying is undisputably true yet you're attempting to skew the facts. The software itself is not worthless. The impedence plot IS worthless. In a real-world scenario (as you have admitted) that graph won't represent the REAL impedence plot. You've already admitted it, and you're continuing to argue. I don't really care what the readers of this thread or forum members think about me. We have both proved me correct. i will no longer be responding because any further discussion is as worthless as your impedence plot.

LBC
10-17-2012, 09:01 AM
The only thing you've proven is that you have a somewhat short temper, and don't like being disagreed with (in which case the interwebs is gonna be a harsh ride for you, my friend).

Clamping woofers at all frequencies - indeed - that takes some time, and I'm sure you've got other things to do - (besides following up with supporting data)... good thing I picked up a DATS, takes it about 10 seconds... :graduate:

For everyone else - here's a couple graphs I grabbed this evening (please forgive the scale between the two being a tad off):

Daily beater box, Impedance plotted in WinISD
http://farm9.staticflickr.com/8046/8095907811_97f30bb275_z.jpg
WinISD is showing a predicted port tuning around the 34hz area (the lowest impedance dip to the right of the peak on the left) with impedance maxing out around the 58hz area

And here's what the DATS actually sampled in the car - (*a few words about that below the graph)
http://farm9.staticflickr.com/8191/8095914670_2ae88dbfc7_b.jpg
DATS is showing a similar shaped curve with tuning in the low 30s, and a shift to the left for the upper impedance peak. Why is this? Cabin gain (aka transfer function), as previously mentioned. Different vehicles are going to accentuate/attenuate different frequencies - and thus affect the impedance of the system.

*concerning my note above, this enclosure weighs around 150 pounds, not going to be able to get a out-of-car measurement at the moment. However, based on my experience, the impedance is going to raise slightly, and the peaks shift to that matching more closely the predicted WinISD curve.

So to sum up, top graph - took about 5 minutes of work at the keyboard.
Bottom graph - took about 3.5 hours of box building.
Now is that top graph 'close enough' for planning a box design? I suppose everyone has to decide that for themselves...

You just proved me right.... again. Do you realize that? I haven't shown a short temper at all. You have merely been lying. Now you have proved as such. Im not sorry that I pointed that out. The impedence, the waveform, the peaks, etc ALL are different. The only thing you can say it "at first glance they sort of look similar". Surely you are trolling me and you are not serious.

n8skow
10-17-2012, 09:37 AM
Lying about what sir?
Your perpetuating this myth that the enclosure can not be planned out virtually before making any sawdust...
My stance from the beginning has been software (in this case WinISD) can give a close enough plot to show where the peaks and valleys are going to be - and thus able to design your box with... WinISD predicted a tuning of about 34hz - and when built to the same specs, the real-world box had at tuning of 32hz (in-car)... 2hz difference - pretty dang close. As I mentioned, I can't pull the enclosure out of the car at the moment, but plotting the response again in the open - the curves are going to be even closer to the projected... What part of this are you taking so much issue with?

LBC
10-17-2012, 09:53 AM
Lying about what sir?
Your perpetuating this myth that the enclosure can not be planned out virtually before making any sawdust...
My stance from the beginning has been software (in this case WinISD) can give a close enough plot to show where the peaks and valleys are going to be - and thus able to design your box with... WinISD predicted a tuning of about 34hz - and when built to the same specs, the real-world box had at tuning of 32hz (in-car)... 2hz difference - pretty dang close. As I mentioned, I can't pull the enclosure out of the car at the moment, but plotting the response again in the open - the curves are going to be even closer to the projected... What part of this are you taking so much issue with?

I made the statement that the real world impedence curve cannot be calculated.... not what you are trying to frame my argument as. Everything you have thus far posted has confirmed what I've said. You are continuing to behave as though you are correct in saying I was wrong. Thus you're lying to save face. You have proven yourself wrong several times. You have accused me of being mad when I'm not. not even close to mad actually. I find your whole charade to be quite entertaining.

Also, winisd predicts the impedence to be highest at the peak frequency of the enclosure. The impedence spikes sub-30 on both of your graphs there. On the winisd prediction it assumes 5.2 ohms. On your "real world" measurement you get to exactly 4 ohms. The winisd predicts about 28hz. "Real world" is about 24hz. You have cited 2hz but your graphs show otherwise. Also the slopes, the bandwidth between peaks, EVERYTHING is different. It not just slightly off. It's quite far off. They simply look similar at first glance. You either have absolutely no idea what you're talking about or you're trolling. I haven't figured out which yet.

n8skow
10-17-2012, 02:22 PM
Nothing in my argument has changed since post #11 (http://www.caraudio.com/forums/usertag.php?do=list&action=hash&hash=11) ... whatever your implying I'm trying to cover up isn't making any sense. We both agree it's not going to be a PERFECT match. I simply pointed out it was going to be REASONABLY close. What you are arguing is a philosophical discussion on what constitutes 'reasonable', which I'm not going to get drawn into.

As I explained - the bottom graph is an 'in-car' reading (which affects the results).
The 'out-of-car' reading will be even closer to the WinISD plot.

The 2hz off I was citing is at port tuning - your looking at the curve below tuning - and yes, it's a bit further off (the 4hz you've pointed out). That's a pretty reasonable margin of error, wouldn't you say? (Again, 5 minutes vs. 3.5 hours... I'll still take option number 1.)

You still haven't disclosed your method for box planning, or shared any notes from your numerous builds to show why this method is so unusable.
In fact, didn't you duck out of this conversation 5 posts ago?

n8skow
10-17-2012, 02:37 PM
Here are the two graphs superimposed over each other - and corrected for scale.
The biggest discrepancies actually being in the higher frequencies - where the transfer function of my vehicle is having a big impact.
Outside of the car, the peaks in the blue curve (DATS real-world recording) are going to move up a bit - and shift to the right.

http://farm9.staticflickr.com/8044/8097685558_7689a3d8dc_b.jpg

I'll see if I can get the enclosure pulled out this weekend and snap another screenshot if your interested in discussing this further...

quackhead
10-17-2012, 02:56 PM
so my buddy says that the smaller the box the less the rise and the larger the more rise.. is this true?

in my modeling software, it shows impedance rising with a bigger box, but not very noticeable inside of 1 cube increments, what is noticeable though are the change in frequencies at which peak impedance rise occurs above and below tuning on a ported enclosure as vb increases or decreases.

n8skow
10-17-2012, 03:32 PM
What program are you using? What woofer(s) are you modeling for?
I'd be interested in seeing your results.


in my modeling software, it shows impedance rising with a bigger box, but not very noticeable inside of 1 cube increments, what is noticeable though are the change in frequencies at which peak impedance rise occurs above and below tuning on a ported enclosure as vb increases or decreases.

quackhead
10-17-2012, 03:54 PM
What program are you using? What woofer(s) are you modeling for?
I'd be interested in seeing your results.

I just pulled up a SSA ICON 15 D1 on winisd in 3 cubes tuned @30hz, it shows @ 1.9 ohms rise at tuning, the pre tune spike is at @ 48hz...same sub in 5 cubes @ 30hz, it shows @ 2.2 ohms rise at tuning and the pre tune spike is at @ 44hz..

LBC
10-17-2012, 04:19 PM
Nothing in my argument has changed since post #11 (http://www.caraudio.com/forums/usertag.php?do=list&action=hash&hash=11) ... whatever your implying I'm trying to cover up isn't making any sense. We both agree it's not going to be a PERFECT match. I simply pointed out it was going to be REASONABLY close. What you are arguing is a philosophical discussion on what constitutes 'reasonable', which I'm not going to get drawn into.
It's not a philosophical discussion. If you care what your rise is(spl only as it varies with frequency and is only necessary to know when you're playing but 1 frequency and NEED it to rise because you're wired uber low), being off at all is unreasonable. It's the difference between killing your amp and it performing normally. Logic > You.


As I explained - the bottom graph is an 'in-car' reading (which affects the results).
The 'out-of-car' reading will be even closer to the WinISD plot.
Out of car matters for nothing. It will never be played there is and completely irrelevant.


The 2hz off I was citing is at port tuning - your looking at the curve below tuning - and yes, it's a bit further off (the 4hz you've pointed out). That's a pretty reasonable margin of error, wouldn't you say? (Again, 5 minutes vs. 3.5 hours... I'll still take option number 1.)
You're claiming that you're getting an impedence peak at just below 30hz and this peak is BELOW tuning? I just want to be clear. You said you wouldn't get involved into a "philosophical debate on what is reasonable" yet you just asked me if being off 2hz is reasonable, even though 2hz is not relevant to the discussion. It's clear that you're full of it and trying to save face.


You still haven't disclosed your method for box planning, or shared any notes from your numerous builds to show why this method is so unusable.
In fact, didn't you duck out of this conversation 5 posts ago?I told you I wouldn't disclose any of my notes on page 1. I did say I wouldn't be back. I changed my mind. I did just win a World Title in SPL Sunday. Does that count for anything?

keep_hope_alive
10-20-2012, 01:09 PM
In the battle of
LBC
vs.
n8skow

decision:
n8skow

reason:
provided data
maintained a mature attitude



I did just win a World Title in SPL Sunday. Does that count for anything?
nope. in this thread your title means nothing. people who don't know you don't believe you until you produce data with documentation.
calculations are only as good as the assumptions you make to derive them. all calculations have assumptions. from your posts, it sounds like you don't understand what is happening and you just use trial and error and get lucky occasionally - which is true for most SPL competitors. if you understood, you would just apply the necessary corrections to the software predictions.
you are welcome to provide results and data to support your claims. your experience is not trivial, the question is if you have been paying enough attention to make it matter.
hell, just write your own modeling software.

it's ok to not understand the physics behind sound propagation at low frequencies in an enclosed space. have you ever solved wave equations? they are a PITA, and developing them takes much longer than 3.5 hours. you could spend 40+ hours developing an accurate prediction for the specific vehicle... if you love physics.

as to the question - is software modeling useful when SPL is the goal? yes - if and only if you understand what will happen once installed in the vehicle and correct the response curves for it. with enough experience and testing you can predict what the vehicle will do to impedance seen by the amplifier. or you can just use trial and error.

the use of tools to measure impedance once installed and compare to predicted is handy, and after a dozen or so iterations you may notice a trend that could be curve-fit - thus increasing accuracy.

goingdef
10-20-2012, 01:44 PM
I would only rely on rise at one tone and for competing as for daily the last amp I tried to predict rise with caught fire while playing music and was producing less then rated power when it did it! so if rise and maximum output are that important to you look into an amp that supply's rated power across a wider impedance range.

LBC
10-20-2012, 02:01 PM
In the battle of
LBC
vs.
n8skow

decision:
n8skow

reason:
provided data
maintained a mature attitude



nope. in this thread your title means nothing. people who don't know you don't believe you until you produce data with documentation.
calculations are only as good as the assumptions you make to derive them. all calculations have assumptions. from your posts, it sounds like you don't understand what is happening and you just use trial and error and get lucky occasionally - which is true for most SPL competitors. if you understood, you would just apply the necessary corrections to the software predictions.
you are welcome to provide results and data to support your claims. your experience is not trivial, the question is if you have been paying enough attention to make it matter.
hell, just write your own modeling software.

it's ok to not understand the physics behind sound propagation at low frequencies in an enclosed space. have you ever solved wave equations? they are a PITA, and developing them takes much longer than 3.5 hours. you could spend 40+ hours developing an accurate prediction for the specific vehicle... if you love physics.

as to the question - is software modeling useful when SPL is the goal? yes - if and only if you understand what will happen once installed in the vehicle and correct the response curves for it. with enough experience and testing you can predict what the vehicle will do to impedance seen by the amplifier. or you can just use trial and error.

the use of tools to measure impedance once installed and compare to predicted is handy, and after a dozen or so iterations you may notice a trend that could be curve-fit - thus increasing accuracy.

Thanks for your opinion. The fact still remains that there is nothing available that can accurately predict impedence rise. The example provided was wrong. If you relied on it and went full tilt for spl you would blow your amplifier. Testing and "getting lucky" would be COMPLETELY required given his examples. So you defeated yourself with your argument and your "vs" statement and conclusion was biased and your assessment of maturity shows your lack thereof since I have done nothing immature. You provided no evidence or factual information which by your definition means you're wrong and should butt out. What you just said was that even though his data proved him wrong, and I showed that, that since I didn't provide any evidence (i didn't need to because his supported my argument) that I'm still wrong and he's right.

quackhead
10-22-2012, 07:31 AM
Thanks for your opinion. The fact still remains that there is nothing available that can accurately predict impedence rise. The example provided was wrong. If you relied on it and went full tilt for spl you would blow your amplifier. Testing and "getting lucky" would be COMPLETELY required given his examples. So you defeated yourself with your argument and your "vs" statement and conclusion was biased and your assessment of maturity shows your lack thereof since I have done nothing immature. You provided no evidence or factual information which by your definition means you're wrong and should butt out. What you just said was that even though his data proved him wrong, and I showed that, that since I didn't provide any evidence (i didn't need to because his supported my argument) that I'm still wrong and he's right.

U mad, bro?













he mad.

LBC
10-22-2012, 10:16 AM
U mad, bro?













he mad.
don't bro me... if you don't know me ;)

bangintahoe
11-11-2012, 02:34 PM
I never really understood box rise

skylineTT
11-11-2012, 02:40 PM
I never really understood box rise

Hardly anybody does.

clickclickw00t
11-11-2012, 09:44 PM
Hardly anybody does.

I thought box rise was how high you raise the box off the floor of your car. needless to say after my local audio shop had a good laugh at my expense, I learned what it really was.

Dirtrider4eva
11-11-2012, 10:05 PM
Impedence rise varies with frequency. At some freqs it actually drops. The reason we call it "impedence rise" is because we only measure it for SPL burps and only at our burp frequency. It means absolutely nothing for most of you on this site who play music through your stereo. It will cause you to damage your equipment.
Impedence rise does not have a predictable pattern or formula to calculate it because as stated, there are quite a few things that can manipulate it.

your impedence will never Drop below the subs wiring however.

LBC
11-11-2012, 10:12 PM
your impedence will never Drop below the subs wiring however.

Please don't say things as truth if you don't know for sure. I know you thought you knew better but you didn't.
"This proves to be very important, since a loudspeaker with a nominal impedance of 4 ohms will sometimes have an actual impedance of 1 ohm or less." -Jacob Fuller of Sundown Audio

Why "daily" systems should not count on impedance rise - SSA Car Audio Forum (http://www.soundsolutionsaudio.com/forum/topic/30610-why-daily-systems-should-not-count-on-impedance-rise/)

keep_hope_alive
11-19-2012, 07:17 PM
Thanks for your opinion. The fact still remains that there is nothing available that can accurately predict impedence rise. The example provided was wrong. If you relied on it and went full tilt for spl you would blow your amplifier. Testing and "getting lucky" would be COMPLETELY required given his examples. So you defeated yourself with your argument and your "vs" statement and conclusion was biased and your assessment of maturity shows your lack thereof since I have done nothing immature. You provided no evidence or factual information which by your definition means you're wrong and should butt out. What you just said was that even though his data proved him wrong, and I showed that, that since I didn't provide any evidence (i didn't need to because his supported my argument) that I'm still wrong and he's right.

i just came back to this thread. you think people should just believe what you say regardless of proof. i don't do that for anyone. neither does the scientific community.

you make statements as fact without supporting information. you may know and are just too lazy to back it up, or you may just be regurgitating information you don't understand. regardless, i have decided to ignore all of your statements until i see a reason to do otherwise.

can box rise be calculated? of course it can. it's just physics. i could write a program to do that if i wanted to spend the time, which i don't, and neither does anyone else.

thevic24
11-19-2012, 07:47 PM
your impedence will never Drop below the subs wiring however.
Umm...

My Infinity Kappa 9 home speakers are wired/rest at 4 ohms.....
they are called amp killers because they are known to dip well below 2 ohms...especially if put into extended mode....

LBC
11-19-2012, 08:19 PM
i just came back to this thread. you think people should just believe what you say regardless of proof. i don't do that for anyone. neither does the scientific community.

you make statements as fact without supporting information. you may know and are just too lazy to back it up, or you may just be regurgitating information you don't understand. regardless, i have decided to ignore all of your statements until i see a reason to do otherwise.

can box rise be calculated? of course it can. it's just physics. i could write a program to do that if i wanted to spend the time, which i don't, and neither does anyone else.

Your idiotic ad hominem attacks do not phase me. Don't think because you're a mod on a dead forum that you deserve any sort of respect. I supported what I said. I simply used someone else's "Facts" to do it. You are criticizing me because you either do not understand what was said, or you have chosen to ignore it. Either way that is your fault and not mine. you called me lazy and wrong and said it's possible, but that you're too lazy to do it. You're nothing more than an arrogant hypocrite. I'm glad you'll be ignoring me.... so you don't continue to make yourself look foolish. Way to dig up and old thread hoping I wouldn't see your ignorance and continue to show you for what you are.

To sum up what he said, "you said there are no programs that accurately calculate rise in a real world install.... that's true but there could be, and I could even write it... but I won't and neither will anyone else". Thus confirming that what I said is true. LMAO.

murph
11-19-2012, 08:26 PM
One time my box rose a WHOLE INCH! The best way to stop it is with L brackets. ;)

keep_hope_alive
11-21-2012, 08:32 AM
I simply used someone else's "Facts" to do it.



you may just be regurgitating information you don't understand.


thank you for admitting it.

if i didn't want you to see my response, i wouldn't have quoted you to get your attention.

keep_hope_alive
11-21-2012, 08:40 AM
Impedence rise does not have a predictable pattern or formula to calculate it because as stated, there are quite a few things that can manipulate it.

this is the main argument you have maintained - that it cannot be calculated.

you feel this way because you don't understand it. you can't calculate something you don't understand.

physics is predictable and can be represented with mathematics.

solving wave equations (differential equations) is time consuming.

no one cares that much about car audio to predict something that can be measured easily.

just because no one bothers to calculate something doesn't mean it cannot be modeled accurately.

my summary is that box rise is better measured than calculated - though you can predict it with enough effort.

LBC
11-21-2012, 09:37 AM
thank you for admitting it.

if i didn't want you to see my response, i wouldn't have quoted you to get your attention.

Your quoted statements didn't prove what you wanted them to prove. You claimed I provided no facts. I made it clear that since he provided "facts" that proved him wrong, there was no need for me to do so. Please try to pay attention from now on.
You waited a month or so to do it, after I showed no activity. It's safe to say you didn't want to get my attention.

LBC
11-21-2012, 09:40 AM
this is the main argument you have maintained - that it cannot be calculated.

you feel this way because you don't understand it. you can't calculate something you don't understand.

physics is predictable and can be represented with mathematics.

solving wave equations (differential equations) is time consuming.

no one cares that much about car audio to predict something that can be measured easily.

just because no one bothers to calculate something doesn't mean it cannot be modeled accurately.

my summary is that box rise is better measured than calculated - though you can predict it with enough effort.
I feel this way not because I don't understand it, but because what I said is true. There are too many variables to take into account. By your own admission no software exists to do it and nobody is going to write it. Even if they did, nobody would fill in enough of the variables to make it accurate. you are arguing it because you don't understand it. If you did, you wouldn't be in here posting. Everything I have said has been 100% accurate and you have failed to demonstrate otherwise. you're just filled with hatred and butthurt and 0 facts. You have tried, you have failed. Move along.

Buck
11-21-2012, 09:42 AM
People really shouldn't worry about rise IMO.

keep_hope_alive
11-21-2012, 11:43 AM
I am walking away from this. I have better things to do than argue with someone who can't back up their own statements with their own knowledge. Anything else can be in a PM.

pro-rabbit
11-21-2012, 11:53 AM
People really shouldn't worry about rise IMO.

Agreed. Unless you are in the lanes fighting for every last tenth of a db, then it is not worth effort to care much. On actual music it will vary so much it is not worth the headache to try and keep up with do to how much it will actually rise/fall under those conditions.