Printer Friendly Forum Posts - best way to face 4 subs

first off wow theres alot of rules to posting on here.

well im wondering whats the best way to face 4 15" subs in my ramcharger. i have 2 in there now but any way i have faced all 4 they cancel echether out.

sorry for the bad spelling thats not my strong pont

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

also i wanted to know where to buy a good SPL meter that goes up to atlest 160db or if any one has a used one for sale

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

1: Thank you for READING them... We get so few that do!

2: They can't. That cabin is so small, relative to those wavelengths, it's an impossibility if they are all phased correctly. How do you have your woofers wired presently?

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

i would think a ramcharger would have plenty of room maybe your thinking its a pick up its like a K5 blazer just dodges version. im not trying to be a pain or rude but most people dont seem to know what a ramcharger is.

any ways there dual 2 ohm hooked to a kenwood 900 wired to 2 ohms at the amp since kenwood amps arnt really 1 ohm stable (tryed it with a set of dual 4 ohm subs)

do i really need to go as far as a wall in this thing i really dont want to because i like to see out my back window lol the total room in the back that i have is 5 foot wide 42 in high and 6 foot long

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

thats only 2 of the subs hooked up i should of spesified i have 2 amps 1 amp for 2 subs

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

i know what a ramcharger is, when you had all four of them in and you said you were getting cancellation, which way were they facing and were they all in separate boxes? 2 subs per box? one big box? you dont need a wall to get plenty loud in that truck, just the right box and you can make them all fire upwards and either port upwards too or port to the rear. if your subs are in prefab boxes right now thats probably half of your problem. oh and you can get the SPL meter by doing a search for Term-Lab meters

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soundnsecurity wrote:

i know what a ramcharger is, when you had all four of them in and you said you were getting cancellation, which way were they facing and were they all in separate boxes? 2 subs per box? one big box? you dont need a wall to get plenty loud in that truck, just the right box and you can make them all fire upwards and either port upwards too or port to the rear. if your subs are in prefab boxes right now thats probably half of your problem. oh and you can get the SPL meter by doing a search for Term-Lab meters

ok sorry about qestioning you about know what the truck is. i have 2 boxs with 2 subs in ech box custom built to memphis specs. i tryed facing them up, stacking them one on top of the other, one behind the other and every time they sound like total crap all most like there blown and 6x9s could pound louder lol take 2 out and its loud so loud it hurts a subwoofer ventrins ears. now i have be installing systems for years but never did a 4 sub setup ony 1 - 2 - and 3 sub setups all side by side facing the same direction and never had this problem. but of corce i cant put all 4 of these side by side.

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

try this, put all 4 subs back in and wire one box backwards and see what that does.

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i should give you some more info on what im trying to do. im starting my own bizz and using this truck so people can hear what my subs can really do. but at the same time if some one wants there subs right after they hear my setup i can take 2 of them right out and put them right in there car. that seems to be the best way to sell these subs since all the kids around here only know the cheapo wallmart brand subs lol i mean i had a set of 14 year old 12" crossfire subs rated at 200rms ech and that was about the loudest any one around here has ever heard. lol

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

soundnsecurity wrote:

try this, put all 4 subs back in and wire one box backwards and see what that does.

really i would think that would make the 2nd set wired backwords botum out in the magnet. i will try it here in a few i gota go real fast and hook up this kids system. any more ideas i can try if that dont work? what way should i face them wiring them like that?

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

moparfan1234 wrote:

soundnsecurity wrote:

try this, put all 4 subs back in and wire one box backwards and see what that does.

really i would think that would make the 2nd set wired backwords botum out in the magnet. i will try it here in a few i gota go real fast and hook up this kids system. any more ideas i can try if that dont work? what way should i face them wiring them like that?

its ok, they wont bottom out just by reversing the phase of both subs in the same box. and besides im not asking you to leave it that way, this is just an experiment to try to figure out whats going on. just hook them up like you had it when you said they were canceling out, and then reverse the wires on one of the boxes. if it gets louder then that is your problem. if it stays the same then i would pull the subs out of the box and check their wiring one at a time to make sure all of the subs are wired exactly the same way. if even just one sub is wired backwards it will throw off everything else.

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Good call, SnS. This is what I was going to suggest. You simply have one set wired backwards, I'm willing to bet.

As an option to "reversing the leads on one set", when you put the second set in, disconnect the OTHER set. Does your bass return? There is your problem. One box has the woofers wired backwards inside the box.

Additionally, it won't matter WHAT the car is, four 12's will NOT cancel each other out, unless there is something wired backwards. If all is wired correctly, you cannot get ANYTHING other than a (roughly) 6dB gain. At those wavelengths, EVERYTHING is a pressure wave in pretty much ANY car.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

so is that why they make a phase switch on an amp is when you run 4 subs you can run 2 back words? i mean is that the way every one has to wire a 4 sub system? i rechecked the wireing there all wired right. (im normaly prity good at geting them wired right the first time) i color code every wire so theres no mix ups.

like i said befor i have never done a 4 sub setup in an SUV most people i have ever known just ran 2 biger and or higher power subs. makes me feel kinda dumb having to ask these kind of qestions im normaly the go to guy but i guess an old dog like me dont know every thing lol

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

ok i also checked them with a 9v battery just incase factory labled them wrong but they all check out right.

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

the phase knob on an amp is for competitors who run massive amounts of subs from front to back. this lets them adjust for subs in different positions so that they can get maximum output at a certain spot where the mic/sensor is to be placed. but, the phase knob is next to useless in a normal setup because it doesn't make that big of a difference.
you shouldn't feel dumb because this is a real problem. something is got to be wrong if you lose output by adding 2 more subs. they are the same make and model subwoofers aren't they? do those amps have a phase switch? if so, are they set the same? are both of your amps set exactly the same?

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soundnsecurity wrote:

the phase knob on an amp is for competitors who run massive amounts of subs from front to back. this lets them adjust for subs in different positions so that they can get maximum output at a certain spot where the mic/sensor is to be placed. but, the phase knob is next to useless in a normal setup because it doesn't make that big of a difference.
you shouldn't feel dumb because this is a real problem. something is got to be wrong if you lose output by adding 2 more subs. they are the same make and model subwoofers aren't they? do those amps have a phase switch? if so, are they set the same? are both of your amps set exactly the same?

yes there the same subs bought all 4 brand new last week built both boxs the same only diff is the amps by 50 watts witch i wouldnt think would make any diff if nether amp is pushing there max power. the kenwood amp has a phase switch is set at 0 and the alpine dont have one. both amps set at 80hz the kenwood is set half way up and no mater how the alpine is set it dont make any diff just turning it up makes it sound worse. i all ways start ajusting my amps from the lowest they go and slowly turn them up. the RCA leads run from the head unit to the kenwood then from the kenwood to the alpine so it all should have the same signal. i even called memphis them selves and and the most they could come up with is run all 4 subs off one amp and see what happens. but then i would have buy anether one and still not be sure if that would fix it.

im gona go try and hook all 4 subs to just the kenwood and see what happens its supos to be 1 ohm stable but i dont need it cranked all the way up to tell if it helped or not. if that dont help in totaly lost. there all wired right i have checked so many times now its not even funny lol

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

well the subs are wired right in the boxs all 4 hooked to just the kenwood and it pounded and i hardly turned it up its gota be in the amps them selves

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

REVERSE THE SPEAKER LEADS ON ONE BOX OR AMP IN THE CAR... trust us on this one. If you hook all four speakers to the Alpine, you'll get the SAME result as you just got by connecting them to the Kenwood!! You are dismissing a possible solution without even trying it. If you don't want to go to all the wiring trouble, flip the damn switch on the Kenwood! Have you even tried that? Also, on the Kenwood RCA outputs... Are you SURE they are just "pass-thru" or are they high-passed on a crossover of some sort? Dude... I'm tellin' ya... It's a phase issue, almost guaranteed!

Seriously. Try it. Just because you are connected positive to positive throughout the system, not every amplifier will be "phase correct" in it's output. Some amplifiers invert their outputs from the input signal. It's referenced to "absolute phase", and if one amp inverts, but the other doesn't, (a VERY good possibility, considering the amps are different brands!) you can experience EXACTLY what you are experiencing.

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It all reminds me of something that Molière once said to Guy de Maupassant at a café in Vienna: "That's nice. You should write it down."

haemphyst wrote:

REVERSE THE SPEAKER LEADS ON ONE BOX OR AMP IN THE CAR... trust us on this one. If you hook all four speakers to the Alpine, you'll get the SAME result as you just got by connecting them to the Kenwood!! You are dismissing a possible solution without even trying it. If you don't want to go to all the wiring trouble, flip the damn switch on the Kenwood! Have you even tried that? Also, on the Kenwood RCA outputs... Are you SURE they are just "pass-thru" or are they high-passed on a crossover of some sort? Dude... I'm tellin' ya... It's a phase issue, almost guaranteed!

Seriously. Try it. Just because you are connected positive to positive throughout the system, not every amplifier will be "phase correct" in it's output. Some amplifiers invert their outputs from the input signal. It's referenced to "absolute phase", and if one amp inverts, but the other doesn't, (a VERY good possibility, considering the amps are different brands!) you can experience EXACTLY what you are experiencing.

dont worry i trusted you man i just needed some one to come home and help carry the 2nd sub box out the door and i had to rewire the alpine amp because i unhooked all wires to the alpine. as you was typing your post i was out hooking up the alpine agan and hooking it back words just like you said. yep you are right they are backwords in the amps them selves. i never new they did that but since you said it i thought well it really could be. i feel its dumb but thats the way it is.

thanks a millon bud

now witch way should i face them now i have them working right? facing up is the ezyest so i can keep my back seat in. also witch amp should i run all the time backwords?

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

well now after all this i think the 4 facing up really ant much louder then the 2 facing back. when i had the back seat out and all 4 of them facing back it was alot louder. idk now im trying to deside if its worth all 4 in there or not because i need the back seat so i cant leve all 4 facing back but talking to people down town with 4 subs vs 2 the 2 would seem more amazing to them. you know where they say wow and thats only 2 subs vs well duh its that loud theres 4 of them.

thanks agan

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

i actually didn't know some amps aren't phase correct, i actually learned something out of all this too. although i knew the whole time that it had to be a phase problem. atleast we got this figured out.

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soundnsecurity wrote:

i actually didn't know some amps aren't phase correct, i actually learned something out of all this too. although i knew the whole time that it had to be a phase problem. atleast we got this figured out.

yea i thought that for a lil bit but then when you said some then it made me think alil more i really tryed to not think it was that befor you said some then but hay it works and i ticked off this kid in town allready with it because he thought his 2 polk audio subs was louder lol well kids must learn some how even if its the hard way i guess lol i love it tho its awsome of all the high end subs i have ever installed and used my self these are by far the best yet even the big bad solo X. i also found out how under rated these memphis subs are i asked them what they could really handle. so it looks like im going for a memphis 4,000 watt rms amp. go big or go home right? lol

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

moparfan1234 wrote:

also i wanted to know where to buy a good SPL meter that goes up to atlest 160db or if any one has a used one for sale

Here's one. I haven't used this type myself, though.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

stevdart wrote:

moparfan1234 wrote:

also i wanted to know where to buy a good SPL meter that goes up to atlest 160db or if any one has a used one for sale

Here's one. I haven't used this type myself, though.

wow lil costly but it looks like it would do the job. any one have some then like that used for sale? befor i brake down and by a brand new one.

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

If you want a mic get a termlab mic. its what every good SPL comp is using now. very accurate. But is does cost a bit more than the one stevdart suggested. It is $650 for a one mic set up but it reads up to 183db you can find it at Termpro.com

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i'd spend the extra money for the Term-Lab over what stevdart showed you. only problem is it is a computer based system so it would be best if you had a notebook pc. but thats what i would get.

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yea i have a laptop thats only 6 months old i was thinking some then around $100 or so it sounds more like i would need to get a used one to get it that cheap. i prity much want one to just compare like sub angles to get the most out of a system it dont really have to be right on with the compation meters just tell me whats better setup. bad part is i know my setup is some where over 150DB other wise i would go buy a wallmart cheapo.

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

oh and did i mention i dont know any thing about what a good or bad meter is or really any thing about them so maybe a lil run down on them would be grate to thanks

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87 ramcharger eclipse CD5000 2 15" memphis M3 kenwood 900rms mono amps

99 dodge cummins diesel eclipse CD4000 1 12" memphis Mclass 800rms audiobuhn amp

the term lab meter is supposedly the most accurate meter there is. it is what they use at most legitimate competitions and for the price you get a lot. the sensor itself is nice but the software is awesome too. you can set it to display just the highest reading so it goes up until to reach your peak spl and then stays there so you dont have to pay attention to the display while you are testing to catch what your peak was. i wish i had the 650 to get one of these because i would just charge people like 5 bucks to meter their system and make my money back eventually not to mention experiment with my own system. it also has an RTA add on kit for sound quality and system tuning.

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