# Subs not hitting as hard after a week?



## jcmsupport (Jan 14, 2012)

I do admit I've been hitting these new Infinity Kappa 100.9 10 subs, 2 of them, wired to 1 OHM rated at 750. RMS for each is 350 and gain is around 3 of 10 on this Fosgate Prime amp. My deck clips the sub at 45 and I never have it past 40, 38 on a daily basis. Now, they all of a sudden don't hit as hard which gave a few ideas on my head.

1 was voltage drops, which is ruled out because running the amp on just the battery alone doesn't effect the sound. 

2 was perhaps it broke in and therefore doesn't hit as hard, possibly tired?

It use to really shake the mirror, now it just semi shakes the mirror and the back massage is not as intense. 

Mind you, these are mid-range subs so I'm thinking it's idea 2. 

What do you guys think?


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## quickaudi07 (May 19, 2010)

Maybe its your amp got tired of pushing your subs so hard, jk, look for bad ground will be a start.

Sent from my SGH-T959 using Tapatalk


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## Aaron'z 2.5RS/WRX (Oct 24, 2007)

My guess is a combination of new gear, not broken in properly or for long enough, coupled with crap power from a Prime amp (Prime is low line for RF) coupled with them being hopelessly overdriven.. Amp model wasn't given, so I'm speculating, but I bet there isn't as much power there as thought.. 

My bet is one of the subs gave up the gost... 

Just because your gain was "low" doesn't mean you wearnt overdriving them from the deck... You say your HU distorts at 45, you drive it at 38-40... What did you test your distortion theory with? a tone? 

Amps amplify, so if you where feeding it garbage, it was amplifing garbage..


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## chad (Jun 30, 2005)

did you blow one of them?


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## minbari (Mar 3, 2011)

could be any of the above or once the subs broke in they shifted the F3 a bit lower and now arent playing as close to the port tune(if ported) as before.


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## chad (Jun 30, 2005)

minbari said:


> could be any of the above or once the subs broke in they shifted the F3 a bit lower and now arent playing as close to the port tune(if ported) as before.


Every single person here has "broken in" a sub, and it's cot a common complaint to have a system go from ripping to "meh."


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## minbari (Mar 3, 2011)

true, just throwing out a posability.


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## Aaron'z 2.5RS/WRX (Oct 24, 2007)

minbari said:


> true, just throwing out a posability.


Same hrrr


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## EmptyKim (Jun 17, 2010)

Check wiring in your subs too, make sure one did not disconnect.


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## spl152db (Dec 20, 2007)

sounds like you blew a sub or wiring went bad or amp channel went bad or rca came unplugged or rca channel went bad or headunit went bad or headunit rca channel went bad or bad rcas or bad speaker wire or sub fell out of the box and is hanging out chilling say sup to its homies. 

subs dont just get "tired" one day.


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## chad (Jun 30, 2005)

^ that too^

Pop em with a 9V battery and make sure they both move,


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## chad (Jun 30, 2005)

spl152db said:


> and is hanging out chilling say sup to its homies.


I WILL find a way to use that at work today.


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## jcmsupport (Jan 14, 2012)

I used a DD-1 to determine gain settings, used the compromise track in which 3 tracks can be selected for SQ or SPL, I did the middle, or the compromise. Also, yes, Prime amp at 1 OHM putting 750. Amp requires a 60A fuse so I assume it's getting the correct power, didn't multimeter it yet. Ground is fine through distro blocks it seems. Both sub move, and are in sync - I'm assuming I just ran the driver a bit.


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## carter1010 (Sep 20, 2009)

when I had this happen I had a bad connection inside my box. Both subs appeared to be working, but in fact were not. It wasn't till I hooked up my multimeter that this was obvious.


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## spl152db (Dec 20, 2007)

jcmsupport said:


> I used a DD-1 to determine gain settings, used the compromise track in which 3 tracks can be selected for SQ or SPL, I did the middle, or the compromise. Also, yes, Prime amp at 1 OHM putting 750. Amp requires a 60A fuse so I assume it's getting the correct power, didn't multimeter it yet. Ground is fine through distro blocks it seems. Both sub move, and are in sync - I'm assuming I just ran the driver a bit.


subs do not get "SICK" or "TIRED" or "LAZY". is it a sealed box? I bet one sub is actually out of phase.. because its blown. or the gain on the amp jumped.


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## chad (Jun 30, 2005)

spl152db said:


> subs do not get "SICK" or "TIRED" or "LAZY". is it a sealed box? I bet one sub is actually out of phase.. because its blown. or the gain on the amp jumped.


subs just don't suddenly jump out of polarity either.


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## spl152db (Dec 20, 2007)

chad said:


> subs just don't suddenly jump out of polarity either.


ah, but they do. when one quits working and isn't seized up, it will move in the opposite direction of the driving sub, creating a small passive radiator, and its since its small it doesn't work right and sucks.


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## HiFiAudioGuy34 (Mar 30, 2011)

Take them out. Check the connections. if all connections are good. Get a multimeter and check the resistance on all voice-coils to make sure you haven't blown any of them. If all of them test good (individually) don't keep them wired in series or parallel when you test the resistance. after that, double check your connections (power, ground, etc.) if everything is cool then test your voltage while playing test tones with multimeter. If you did all of the above with no bad tests I'd get the amp checked out.


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## chad (Jun 30, 2005)

spl152db said:


> ah, but they do. when one quits working and isn't seized up, it will move in the opposite direction of the driving sub, creating a small passive radiator, and its since its small it doesn't work right and sucks.












It's really not OUT OF polarity, it has NO polarity.. or damping


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## spl152db (Dec 20, 2007)

yet would still cause this problem.


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## chad (Jun 30, 2005)

spl152db said:


> yet would still cause this problem.


it is the most likely scenario. IMHO.


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## passtim (Sep 30, 2009)

AND,,,,,,,,,,,if both subs are working and wired correctly, it could be that the mounting hardware (IE SCREWS) may have worked themselves loose, loosing your seal (IF a sealed Box) so just tighten them and see if this solves the issue.


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## jcmsupport (Jan 14, 2012)

I's a ported, I believe 2.66 cubic feet total so 1.33 per sub (Memphis Audio Prefab). Infinity recommended 1.50 but eh, it fit in my Mustang trunk so I can't complain. What's cool about these subs is that they have selectable impedance either 2 or 4 OHM, perhaps the switch actually switched inside the box for one of them. I'll multi-meter them right now.


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## jcmsupport (Jan 14, 2012)

Resistance seems fine - doesn't go off the rails - fluctuates between 1.5 and 0.7 because of the cheap multimeter.










Although I did get into car audio just this last December, the wiring should be ok - I'm using 12 gauge Knukoncept wiring. DMM them prior to screwing them in.










Sure wiring is a bit disorganized, but it works, everything seems ok.



















The setup - No alternator noise, 6x8 Kappas all around - My guess is the amp or the drivers but most likely the amp. Mind you, this is street stock, no HO alternator, using a Duralast battery from Autozone ATM.

So it would be wise to test the amp using the multimeter. What setting should I have it at for testing the voltage on the amp via the DMM? I can research the formula once I know the setting and the numbers. What test tones should I do? I really appreciate all the input guys, I mean, literally, I appreciate you guys, I love this audio ****.


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## chad (Jun 30, 2005)

you disconnected the amplifier from the speakers when you measured resistance correct?


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## jcmsupport (Jan 14, 2012)

chad said:


> you disconnected the amplifier from the speakers when you measured resistance correct?


Yes, removed the wire coming from the amp to the box. Simply put the probes within the T-cup of the box and determined resistance that way.


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## chad (Jun 30, 2005)

It's not very often you see the DCR of the drivers be equal to that of the impedance. I mean, it's possible, but DCR is usually lower.


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## jcmsupport (Jan 14, 2012)

Ya, it goes from 1.5 down to 0.7 and bounces, etc. But that simply tells me resistance is indeed ok, I think it may be the amp, it would be pointless to DMM each sub at this point?


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## carter1010 (Sep 20, 2009)

Set the multimeter to voltage. Disconnect the speakers. Turn off all your crossovers. Get a 0db test tone, 40 or 50 hz should do, then put the leads of your multimeter on the positive and negative output of your amp. I do this with the car running for the most voltage input. If you are doing 750 watts that would be 27.39 volts on your multimeter.


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## carter1010 (Sep 20, 2009)

jcmsupport said:


> Ya, it goes from 1.5 down to 0.7 and bounces, etc. But that simply tells me resistance is indeed ok, I think it may be the amp, it would be pointless to DMM each sub at this point?


I have had impedance jumps when outside due to wind or vibration, but that was on my fluke and its quite senstive. I have found that cheaper multimeters typically don't respond to those small fluctuations due to environment. You might have a bad coil. I would take the subs out and test one coil at a time for sure at this point.


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## jcmsupport (Jan 14, 2012)

carter1010 said:


> Set the multimeter to voltage. Disconnect the speakers. Turn off all your crossovers. Get a 0db test tone, 40 or 50 hz should do, then put the leads of your multimeter on the positive and negative output of your amp. I do this with the car running for the most voltage input. If you are doing 750 watts that would be 27.39 volts on your multimeter.












According to my multimeter above, what setting would be proper to test my amp voltage? I should turn the dial to? 

After I test voltage, I'm going to take the box out and test each coil, they are single coil subs.


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## carter1010 (Sep 20, 2009)

jcmsupport said:


> According to my multimeter above, what setting would be proper to test my amp voltage? I should turn the dial to?
> 
> After I test voltage, I'm going to take the box out and test each coil, they are single coil subs.


AC voltage. All you want to do is to make sure that your amp is at least doing rated power.


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## jcmsupport (Jan 14, 2012)

carter1010 said:


> AC voltage. All you want to do is to make sure that your amp is at least doing rated power.












So it would be the ACV with the line above the V right, red area? 200 or 500?


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## carter1010 (Sep 20, 2009)

jcmsupport said:


> So it would be the ACV with the line above the V right, red area? 200 or 500?


Start with 200 since you will be measuring a much lower voltage than that.


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## jcmsupport (Jan 14, 2012)

So using the ACV 200 Red Section setting - results are:

50HZ Bass Test Tone / 23.4 V / 38 out of 50 on Head Unit
50HZ Bass Test Tone / 29.6 V / 40 out of 50 on Head Unit

It seems my amp is ok according to the multimeter. Just replugged the sub and ran the same 50HZ tone and they seem to be in phase. I'm assuming one of them or perhaps both of the drivers are blown? I mean, the drivers can be blown and the result would be a semi-performing sub or death in which the cone won't move at all right?


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## spl152db (Dec 20, 2007)

chad said:


> I WILL find a way to use that at work today.


Did it happen? I want stories!

Sent from my ADR6400L using Tapatalk


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## chad (Jun 30, 2005)

spl152db said:


> Did it happen? I want stories!


I searched long and hard, I'll bet today/tomorrow I find it.. I have to meet with architects and planning engineers all damn day today so... Make your own case.


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## minbari (Mar 3, 2011)

jcmsupport said:


> So using the ACV 200 Red Section setting - results are:
> 
> 50HZ Bass Test Tone / 23.4 V / 38 out of 50 on Head Unit
> 50HZ Bass Test Tone / 29.6 V / 40 out of 50 on Head Unit
> ...


not likely. if they are playing, then they are not blown. blown VCs dont play at all and it you banged the **** out of em they would be making weird noises. the fact that they play test tones fine...........the ohms out ok.....your amplfier voltage is good. everything is working as well as it can.

simply, the subs broke in and now they dont quite play as loud.


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## chad (Jun 30, 2005)

If that's the case then it's the weirdest sub break in I have ever heard of.


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## minbari (Mar 3, 2011)

chad said:


> If that's the case then it's the weirdest sub break in I have ever heard of.


not saying it makes sense. but you have to admit, all his tests check out.


*whsipers* could be hearing damage and it just doesnt sound as loud to HIM


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## spl152db (Dec 20, 2007)

no all his tests didn't check out. the meter couldn't hold a steady resistance reading. unless he was pushing on them it shouldn't have been jumping like that. We know at this point the amp works. I would pull the subs and meter and test each coil with a battery to see if it works. or at least use continuity test.


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## chad (Jun 30, 2005)

minbari said:


> not saying it makes sense. but you have to admit, all his tests check out.
> 
> 
> *whsipers* could be hearing damage and it just doesnt sound as loud to HIM


Some people get used to things after the wow factor wears off also.

If not we would still be rocking 386 processors..


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## minbari (Mar 3, 2011)

a .3ohm flucuation is not enough to worry about IMHO. a truck driving by could cause that much change. remember speakers are also microphones. sound will induce change.


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## chad (Jun 30, 2005)

minbari said:


> a .3ohm flucuation is not enough to worry about IMHO. a truck driving by could cause that much change. remember speakers are also microphones. sound will induce change.


yup, such in fact that the down and dirty method of testing for an open coil inthe feild is to drag your keys across the input terminals (*creating a rough intermittent short) while moving the cone up and down with your hand.... listen.

Hear noise? Speaker not open. Hear no noise? Speaker open.


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## HiFiAudioGuy34 (Mar 30, 2011)

I've read stories about the selectable (switches) impedance on woofers from infinity were sometimes (pretty frequently) faulty. IF it were the case IT WOULD MAKE TOTAL SENSE. If you hit a bass note that rattles the switch from 2ohm to 4ohm your resistance just doubled from a total impedance (which in theory: cuts your output in half). take the subs out and test them separately(my first suggestion) heck test the playing resistance at the amp. Or call harmon kardon and see about warranty.


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## spl152db (Dec 20, 2007)

minbari said:


> a .3ohm flucuation is not enough to worry about IMHO. a truck driving by could cause that much change. remember speakers are also microphones. sound will induce change.


actually he was saying 0.8 (0.7 to 1.5) thats a big difference. HUGE in fact.


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## HiFiAudioGuy34 (Mar 30, 2011)

spl152db said:


> actually he was saying 0.8 (0.7 to 1.5) thats a big difference. HUGE in fact.


^x2 I guess I scrolled right past that post. so yeah it looks like the defects are applicable in your case OP  Call harman and see about warranty.


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## minbari (Mar 3, 2011)

spl152db said:


> actually he was saying 0.8 (0.7 to 1.5) thats a big difference. HUGE in fact.


call it huge if you like. put a multimeter on a sub and tap it. will move around like nuts.

still a good idea to test the sub individually, but I doubt he finds anything.


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## Aaron'z 2.5RS/WRX (Oct 24, 2007)

minbari said:


> call it huge if you like. put a multimeter on a sub and tap it. will move around like nuts.
> 
> *still a good idea to test the sub individually*, but I doubt he finds anything.


 
This...


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## spl152db (Dec 20, 2007)

ever decide to keep troubleshooting your issue? or basically decide you blew an eardrum?


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## jcmsupport (Jan 14, 2012)

I'm going to test it out tonight. It's just I live in an apartment complex where it's 3 flights of stairs and it's just a pain to lug them up there. I'll test resistance for each sub and post later tonight. Worse case if one fails or both are indeed ok, I'm going to sell them and just get some Type Rs \

And no, my hearing is legit. I really based it on how my rear view mirror moved. You could see the waves in the mirror, and with it at desired volume/voltage - it would shake the mirror, it gave it a better presentation. Now, the mirror isn't so dynamic, and my seats simply don't give me that back massage it once did. I didn't have a decibel meter to determine SPL but you just notice those things, it simply doesn't hit as hard is the phrase.


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## hilander999 (Jul 6, 2011)

jcmsupport said:


> I really based it on how my rear view mirror moved. You could see the waves in the mirror, and with it at desired volume/voltage - it would shake the mirror, it gave it a better presentation. Now, the mirror isn't so dynamic, and my seats simply don't give me that back massage it once did. I didn't have a decibel meter to determine SPL but you just notice those things, it simply doesn't hit as hard is the phrase.


I hate to be the one pointing out obvious contibuting factors to tactile vibrations from sound waves, but no one has addressed a few critical points the adversly effect non directional transient bass tones.

Did you change *ANYTHING* about your car when the subs performance droped?

Here's a couple things that will always effect tactile audio response...
-Opened Windows vs. Closed windows
-Crossover points/slopes for SUB
-Crossover points/slopes for front midbass
-Time Alignment/Phase for front stage vs. SUB
-Phisical wiring polarity of any speaker playing in the same frequency range.
-Accoustic treatment/CLD/MLV/CCF
-Back seat open or closed.
-Rear speaker backwaves canceling out sub in closed trunk
-Rubber vs. Carpet floor mats
-Dash pad vs. stock dash
-Fabric seat covers vs. Leather/vinyl
-Cabin Temperature/ Extreme cold vs. Normal temperature
-Tightly sealed cabin/ heater on high vs. heater off.
---Higher cabin pressure slightly reduces speaker cone movement and increases wave compression and cancellation in simular frequency ranges.

I've not seen where you describe your vehicle or any details about the rest of your system. There's a lot more that determine how a sub responds then just the amp/sub combo. Anything that changes the cabins accoustic reflections will change the way your system sounds and how its tuned.

My recient install has taught me more then I ever wanted to know about car audio. The slightest change to anything in the car can drastically change how you need to tune your system.

If I change the crossover point on my amp to the front mids by 2 clicks either direction, my mirror does not jump around like crazy. which for me is a plus since I'm using tactile transducers to reduce the need for large subs in my trunk. I dont really like my mirror jumping around, but do like to feel the kickdrums.

Running more then one crossover can be detrimental if not dialed in properly, the example here would be setting XO on the HU and the AMP/DSP.

Tell us more about your vehicle and how your system is setup.

Check the subs individually out of the box.

If everything looks good, then its definately time to TUNE YOUR SYSTEM, how this is done will depend greatly on what gear you are using. Most of the time all it takes is swapping the polarity on one midrange, changing the phase of the sub vs. front stage, or a couple clicks on the amps crossover settings.

Nothing is ever as simple as we would like it to be, with that said, if you actually got the whole way through this post (long winded) and think I'm an idiot, then just ignor it and buy better subs.


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## jcmsupport (Jan 14, 2012)

hilander999 said:


> I hate to be the one pointing out obvious contibuting factors to tactile vibrations from sound waves, but no one has addressed a few critical points the adversly effect non directional transient bass tones.
> 
> Did you change *ANYTHING* about your car when the subs performance droped?
> 
> ...


No, by all means, I appreciate the input. Sure, all of the specs have not changed other then EQ settings which would determine volume of my sound stage. 

Basically once I dialed it all my crossover settings, them being 120 HZ for my front stage, 100HZ for my rear stage, and 80HZ for my sub, I was set on the "sound" of the subs. Changes stated above would only be maybe the windows being down as oppose to up and having my rear seats down or up.

Now in terms of my mirror, I believe this was a direct reflection of the tones hitting the chasis and would resonate throughout the whole car with rear seats down or up. Decibel level would only change when seats were down, it simply would be louder as I'm allowing more air to flow, "boomier". This in no way changed how the mirror moved having the streets up or down.

Mind you, I've looked into all those factors, but you have to realize what you are mentioning are subtle factors. The change in how the mirror moves is distinctive. I believe it's totally the hardware at fault here. I'm going to test resistance tonight once the girlfriend comes over.

I understand these Kappa 10s are midrange, and are indeed made in China. It's been nothing but RMAs with Infinity and my luck. So maybe it's time to just ditch Infinity and go Alpine or RE, known brands that simply can stand the abuse. Perhaps they are also made in China, but just of better quality.


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## hilander999 (Jul 6, 2011)

jcmsupport said:


> No, by all means, I appreciate the input. Sure, all of the specs have not changed other then EQ settings which would determine volume of my sound stage.


EQ settings are not for controlling the volume of your soung stage, they are meant to tame dips and peaks in the frequency responce in relation to the room they are in, which in this case is an unknown vehicle of some kind.
*What vehicle do you have?*



> Basically once I dialed it all my crossover settings, them being 120 HZ for my front stage, 100HZ for my rear stage, and 80HZ for my sub, I was set on the "sound" of the subs. Changes stated above would only be maybe the windows being down as oppose to up and having my rear seats down or up.


120HZ is rather high for a front stage including midrange drivers because lack of response below about 70hz in the front stage is going to localize bass hits to the rear of the car, which is the opposite from what most people strive to achieve. My front mids are crossed at 60hz with the sub out of phase to them for a dry bass effect which removes directionality of bass tones all together.



> Now in terms of my mirror, *I believe this was a direct reflection of the tones hitting the chasis *and would resonate throughout the whole car with rear seats down or up. Decibel level would only change when seats were down, it simply would be louder as I'm allowing more air to flow, "boomier". This in no way changed how the mirror moved having the streets up or down.
> 
> Mind you, I've looked into all those factors, but you have to realize what you are mentioning are subtle factors. *The change in how the mirror moves is distinctive.* I believe it's totally the hardware at fault here. I'm going to test resistance tonight once the girlfriend comes over.


Your assumption sounds like it should be accurate, and certainly seems to make sense, but is hindered by a misunderstanding of basic physics. Sound waves do effect what they hit to one degree or another. Take a large glass about half full of water and hold it in your hand about 2 feet in front of your subs playing at your normal listening volume. Notice how much movement you see in the water caused by the high pressure sound waves hitting the glass, and this is with no physical connection to the source of the tactile vibration at all. Your rear view mirror is less stable then the glass of water you are holding and is also receiving direct contact movement from the physical attachment to the windshield.

While you are still noticing movement in the mirror, these effects would be more violent when hit by both the mechanical transmission of vibration through the chassis and the reflecting sound waves at the same time. If the front stage is fighting with the sub stage, these waves are being canceled out which will greatly reduce the overall tactile bass response.



> I understand these Kappa 10s are midrange, and are indeed made in China. It's been nothing but RMAs with Infinity and my luck. So maybe it's time to just ditch Infinity and go Alpine or RE, known brands that simply can stand the abuse. Perhaps they are also made in China, but just of better quality.


I can't comment on the quality of subs I've never heard.
There's always "Bigger and Better" but that does not mean they will not suffer the same as what you have now, if it's a tuning issue.

*Post the specs of your system in great detail, including the crossover settings/slopes you are using and where they are set. *
Without knowing the *exact system design*, no one will be able to troubleshoot this type of issue and if it's not a fault in the subs you are running, then you will be upset about spending money you did not need to spend while still having a simular problem with new equipment.

*Have you tried reversing the polarity of your subs?*

FWIW: I only have an 8" sub in my trunk, with the tactile trasducers turned off my mirror vibrates like a mother trucker if the phasing is not correct, which in my case was 160degrees on the phase control for the sub. If I run it at zero degrees the bass feels like its hitting the back of my seat, not the whole car like it should. My goal was a dry bass effect, which seems to be the opposite from what you are trying to achieve.

Tuning an audio system is an art, and I'm not even going to pretend I understand half of it because I learn new things all the time which has greatly changed how I view the system design portion of a car audio install.

If your current subs are not up to the job, by all means replace them, just understand that the rest of the system has a lot to do with how they perform.

Good Luck.


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## jcmsupport (Jan 14, 2012)

4 6x8 Kappas in a 07 Mustang. Front stage is 120HZ simply due to too much midbass from the 6x8s in the front. 6x8s in the rear are 100HZ and the 2 subs are in the trunk, using a 2.66 cubic feet box, 1.33 each sub and those are set at 80HZ. JVC KW-AVX640 is the head unit and all crossover settings are via the headunit which totally disregards the amps settings. I have not tried and reversed polarity, should I try that too and see if it affects it? Perhaps, just reversing the +/- wires to the amp? Slopes I have no idea, I just set the headunit to those options above and it displays the slope for me.


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## Oliver (Jun 25, 2007)

Sell em and buy something else


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## jcmsupport (Jan 14, 2012)

SO I finally got them out! Let's test resistance per sub now. Taking them out, both impedance switches were in their right place, no sign of movement from them.




























Taking them out, checking for loose wires, etc. Everything was proper when looking at the wiring, tight! Using 12 gauge Kicker wiring wired at 1 OHM. Came out reverse even though I rotated it via Photobucket, oh well.










Left sub resistance check - switched between 2 and 4 OHM and all checked out fine.










Right sub resistance check - switched between 2 and 4 OHM and all checked out fine.

Prior to taking them out, I switched polarity via the amp wiring, + to - and vice versa, and no change in sound. Tried 180 phase change, again, no different in how the subs hit. I think bottom line with the amp check, resistance check, we can all conclude perhaps the subs are just "tired" and/or cheap. I think I'm going to just sell them and get Type Rs, I have nothing to lose right.


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## hilander999 (Jul 6, 2011)

How exactly are they wired?
I see 2 terminal blocks on the enclosure, are they wired seperate from each other?
And if they are wired straight from the sub to the terminal blocks, what the extra wire for?



> Prior to taking them out, I switched polarity via the amp wiring, + to - and vice versa, and no change in sound.


Something is fishey here, there is ALWAYS a difference in the sound at a given location (drivers seat) when swaping polarity (phase).



> Tried 180 phase change, again, no different in how the subs hit.


Swaping the wires at the amp IS changing the phase by 180 degrees. Does your headunit have a phase adjustment for the sub output?

What crossover slopes does your HU give you? (6/12/24/36...)


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## 07azhhr (Dec 28, 2011)

hilander999 said:


> How exactly are they wired?
> I see 2 terminal blocks on the enclosure, are they wired seperate from each other?
> And if they are wired straight from the sub to the terminal blocks, what the extra wire for?


 
I am wondering the same thing. 


OP - try hooking the wires all back up the way you had it running and test the ohms at the amp connections (AMP NOT POWERED UP). You don't have to have the wires connected to the amp but check the ohms at the end of the wires where they would connect to the amp.


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## Wesayso (Jul 20, 2010)

hilander999 said:


> Something is fishey here, there is ALWAYS a difference in the sound at a given location (drivers seat) when swaping polarity (phase).


Maybe not as much difference if you only "read" the mirror shake to determine its output. 

I think the mirror shake will be at it's highest in a small frequency range. You just have to find out which range that is.
A better indicator would be a simple SPL meter. I can make my floor boards "dance" with a single sealed 8" sub if I up the level of 20 Hz on my EQ. It's only a resonation, it's not how loud it actually plays. Turn down 20 Hz a bit and it takes away the resonation. I turned down 50 Hz as well as that makes a lot of things vibrate. But I know what level it plays at these tones with my simple RadioShack SPL meter...


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## jcmsupport (Jan 14, 2012)

Everything checks out, just going to put it back in my car, and determine HU slopes.


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## hilander999 (Jul 6, 2011)

hilander999 said:


> How exactly are they wired?
> I see 2 terminal blocks on the enclosure, are they wired seperate from each other?
> And if they are wired straight from the sub to the terminal blocks, what the extra wire for?
> 
> ...


No answer to these questions?


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## jcmsupport (Jan 14, 2012)

hilander999 said:


> No answer to these questions?




My HU doesn't really display what you are asking.


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