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sp4 dust cap warm

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i just got my sub hooked up and my chasing electrical issues. while testing the sub i noticed the dust cap got very very warm, to the point of me wanting to pull my hand away when i touched it. the sub was not reaching xmax and was also not fully powered.

 

i have the sub wired as follows to a ZX2500.1. now i noticed that the kicker amp flashes protect when the bass hits but its not constant. so i expected there to be a grounding issue. i ran all new 0ga power and ground using 5/8" brass bolts and nuts and 1/8" brass flat washers on a freshly grinded clean section of my frame rail. im replacing my alt wire to 0ga and am looking into a new alt. all this said i feel that the dust cap issue is unrelated to the grounds.

 

now i have had some extensive courses in digital design so i thought i would put them to use in building a 2D model representation of my 3D diagram i built on how i wired my sub: please do not comment on my skil as an artist as i know im very good. i am however interested i knowing if this is wired correctly for a 2 ohm load on a dual 1 ohm coil sub.

 

7gas4U4.jpg

 

 

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Wiring is right..

 

The dustcap is going to get warm, that's the air pump for the cooling system. So long as you aren't smelling anything you're fine.

 

Have you upgraded your electrical system? If so what have you done? What batteries/alternators?

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Missed you're hunting for an alternator.

 

Look up Singer alternators, Mike is good people.

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i have 0ga grounds from both factory batteries to the frame, 8ga to the body and 4ga to the block. soon to be 0ga alt to battery i think. i built a copper distro block out of 3/8" plate that both batteries connect to and then fuses off of that to all my parts. i wounder if i should run the alternator charging wire to the batteries, to the factory fuse block location or to my custom fuse block?

idk what alt im buying yet. batteries are 2 group 31 975CCA with 140CA reserve and 120AH. sub amp is 0ga ground/power, tweeter amp is 8ga power/ground, and mids amp is 4ga power/ground.

 

all terminals soldered. battery terminals are 5/8" brass bolts and flat washers with all wires bolted down via ring terminals to teh battery stud.

 

 

 

 

pic: AEQAWdk.jpg

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so the dust cap getting hot when at max power is not a concern? it gets very hot. i never felt my BL dust cap as it was a rear firing so i never had access to it. i do smell the sub but its the same smell ive had from all my speakers when i push them for as long as i can remember, home audio or car audio alike. that new sub smell i suppose. 

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The carbon is a way better conductor of heat so it's definitely going to feel hotter. Some excess glue is going to burn off of the coil as it has to cycle a few times before it gets 'burned in' if you will.

 

If you're still running lead acid batteries that's something you should definitely replace before doing the alternator. If your truck came stock with dual batteries that's all it's made to run, it's not made to run a 2500++ watt stereo on top of that.

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the factory alt is a 223A and the batteries are semi truck batteries. AGM are much more expensive and from what i read can not be used on a normal charging system and must be charged slowly so i would have to plug them in each night. if they cant charge from a the high output of an alternator im not sure i want ot go that route or even need to. i would think that 2 or 3 975CCA batteries should be able to handle a meer 2500W stereo. 

 

i am just not sold on the idea of spending 2200.00 on 3 kenetic batteries.

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Ran AGM batteries daily for many years..you can't overcharge them..that will hurt them.

 

If you run an alternator with an external regulator, or one that charges 'dumb' per se without a control module you will run into problems..but you'd still boil the lead acid battery over anyhow if that were the case.

 

XS Power batteries aren't even that expensive, SSA sells them in the store here!

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hmmm, so the alt just gets some new charging system and then its good?

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Put it this way, if your alt never charges above 14.4v once hot.. it would take a miracle for your regulator to overcharge an agm battery in mexico weather.

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4sxpower in incorrect. i has listed me a group 27 battery while mine takes 2 group 31's

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so how do the chargers work? do i hook them between the alt and the batteries?

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i love how this question of "my cone is getting hot" ended in the sub setting fire to my truck...

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Subs only convert a few % of the power they are given into acoustic energy, the rest is heat.  Your 2500 watt amp is making the sub dissipate well over 2000 watts of heat.  That is why the dust cap is getting hot.  Some subs don't have a good thermal connection to the dust cap, yours does, that is why it gets so hot.  In reality, it is just helping with heat dissipation.

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i just got everything hooked back up and the cap is still getting warm. its not burning hot like it was before but it is warm. is there a certain temp i can set as a threshold? i can use a ir thermometer on the cone as the sub is running to monitor its temps.

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I wouldn't worry about.

 

Additionally, there isn't a man alive that can tell you exactly the temp threshold of the dustcap before thermal breakdown of the voice coil, just too many damn variables.

 

Don't overthink this.  Use your nose and ears.  Also, don't forget that REGARDLESS of your settings, that amp can produce WAY more power than that SP4 is thermally rated for...

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how? i dont understand this. the amp is a 2500W, 2800-2900 at 13.3. the sub is 3KW and ive added the cooling so 3200-3500W should be no issue for this sub. 

 

in either case with out bass boost the sub has no kick to it at all so idk... i feel like im not understanding any of this. there is no conceivable way that this amp can provide enough power to over load this sub on a non clipped signal. so i dont understand what you are saying?

 

do i need to buy a 5KW amp so i can provide proper power to this sub with out bass boost? i can do that, ill go out and buy a BC5000.1 tomorrow if that will allow me to use this sub to its full potential. 

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how? i dont understand this. the amp is a 2500W, 2800-2900 at 13.3. the sub is 3KW and ive added the cooling so 3200-3500W should be no issue for this sub. 

That amp can produce way more than rated when clipped.

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That amp can produce close to 5KW of power, with the right signal.  It doesn't necessarily need to be clipped to do that.  This is more than that sub is rated for.  Also, all clipping indications from the amplifier itself are just based on a comparison between input and output signal.  You can run a heavily compressed signal into the amp, it will produce well over 2.5KW and there will be no indication whatsoever of clipping.  Also, clipping in itself doesn't hurt anything, at all.  It never has.

 

What you need to understand is that you can easily fry that sub with your amp.  It is immaterial how you get to that point, just know you can.  There is nothing wrong with using bass boost, eq, etc.  You just need to understand that you have the potential to overdrive the subwoofer.  Be smart, if you hear distortion, turn it down.  If you get to a point where you keep turning up the volume, but it isn't getting any louder, you need to stop.  When you get burning heat smell, turn it down...  It is just a little common sense, that's all...

 

BTW, it should be loud as hell with that amp in a vented enclosure.  If it isn't, something is goofed up somewhere, seriously...

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i dont want to use bass boost. the whole idea of bass boost seems stupid to me now that i have looked into it more. boosting db at 40hz and no other frequency?

 

with bass boost off i dont get volume. it sounds like my 15" vidsonix and at most im using 5-10% of xmax on the sub.  when bass boost is turned up the volume kicks in and i get much more movement out of hte sub but the cone gets FU**ING hot. 

 

im going to install an amp meter into the power line of hte amp to see what its pulling in real time.

ill go to my local audio shop and get the amp bench tested monday

i want to monitor the sine wave coming out of the amp and record it on a computer. how would i go about doing this?

 

im sick and tired of being in the dark, i want to stop "using common sense and going by ear" and i want to get some hard, raw data on this so i can dial this in mathematically and if/when something blows up i will have data to tell me what it was doing at that moment. 

 

i do not feel that this amp/sub setup is doing what it was built for and i do not feel that this amp is putting out any power with bass boost and gains down. should an amp not be able to put out rated power with out its gains up? if gains kill subs why would i want to turn them up at all?

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I have no idea where you are getting your info, but it sounds like you are being miss-led. 

 

You need to take a step back and think about what you are doing.  Research what the amp gain is for.  Research cabin gain and most musical material content before you judge the usefulness, or uselessness of your bass boost.  Also, you need to get someone who knows what they are doing to help you out.  Something is wrong with your install, and it will be mental masturbation trying to figure it out on the internet...

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I think what everyone is trying to say, is that there is a problem somewhere that we can't see.  That sub shouldn't be getting that hot.  If you insist on using the gain as a wattage knob, it might get warm.  You can never add enough electrical upgrades.  Turn your head to that aspect, then work your way to the amp. 

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part of my "information" is the white powder from the fire extinguisher that's still stuck in my upholstery of the truck cab... 

 

let me run through this here and see what you guys think, a local car audio shop wants to hire me to do installs so if/when that happens i will have access to more equipment to play with.

 

now let me start by saying that this sub got bloody loud, when i went to the audio shop to show it off there were customers there who had there SUV's full of subs 3 or 4 12's and when i turned mine up they walked over to see what in the fuck was setting off alarms down the block. 

 

now lets go to what my actual goals are - this is where things get complex. i prefer bass in the higher frequencies (45-80hz) but i dont want to be missing the 30-44hz range so i want these to be more balanced. even at max volume the SP4 was not loud enough for me. now it should be said that installers at the audio shop did not want to stand near the truck for to long as it was "to loud for them". 

 

I am looking for bass that is clear and musical while at high volume can shatter my windshield and provide enough air to eject things from the truck cab.  the first box i had for this was to small cubic and to high a tuning. had great high bass but zero low end as the sub was unloading at around 39hz. second box had a messed up port that caused muddy bass. this box is fixed and is tuned to 32hz at 7.2cubic.

 

I have mechman 280amp alt, knu conceptz 0ga and OFC for long runs. 4 group 31 liquid batteries, all cables bolted directly to the battery studs with brass washers and bolts, all wires soldered with electrical solder and copper ends. amp grounds to the frame and frame has been ground down to metal for good contact. wires going into amps have shielding cut back and the strands pushed in and the set screws cranked down. longest wire run is about 12ft.

 

head unit is pioneer with shielded RCA's going to a KX3 and then out to there respective amps. the ZX2500.1 does not go through the xover as i think its got the same xover built into it, no?

 

the alt has 0ga ground and power going directly to the battery. the amps all connect to a 3/8" plate of copper that is a common link between all the batteries and this has sets of ANL fuses coming off it.

 

the box is 1.5" mdf build with 45 corners, a rounded port opening, glue and screws.

 

8ga wire from amp to sub.

 

now i noticed today that when i turn my decks EQ up on the 100hz range that my tweeters distort. why is this? they are xovered at 4.5KH on a very expensive xover. i should be able to push the 100hz up to 50 and still not get any bass to the tweets.

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I am totally confused.  You went from "sub has no kick at all" to "this sub got bloody loud and setting off car alarms"

 

If it is bloody loud and walking all over multiple sub set-ups, what is the problem?  The dust-cap gets warm, I get that.  Have you leaned on it for any length of time?  It hasn't blown yet, right?  You have a decent amp that does 2.5 KW, right? 

 

I guess I don't see the major problem, but I am not getting consistent info from you.

 

Is it not loud enough or are you just worried about the dust cap heat?

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