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brooklynjoy2008
10-28-2011, 04:57 AM
If I fire 3 10s front and 2 back with ports back will they cancel each other out? Its in the trunk of a 2000 alero and I was just wondering if this was practical or if they would cancel each other out?

disturbed471985
10-28-2011, 05:02 AM
Not real sure what you are trying to accomplish with that type of setup but I dnt think u will have a canceling issue you may run into some other issues though. Why such a weird box sometimes more does not always mean better..

subzero
10-28-2011, 07:28 AM
it probably wouldnt if the rear subs where inverted or had reversed polarities. but personally, I would spend the extra money and just 2 twelves or 2 tens that really get down.

brooklynjoy2008
10-28-2011, 09:44 PM
I will be competing and i can use 3 12s which would give me 339 cone area and a 60 amp fuse but with 5 10s i have 390 cone and still my 60 amp fuse. Am i right in thinking i will have better results like this more cone area should be louder right? I will be using re *** 10d4 subs on around 3000 rms this will be my first build so im not real sure about some things so any help would be appreciated

NoLoud4U
10-28-2011, 09:46 PM
I doupt you have enough airspace for 5 10s.

brooklynjoy2008
10-28-2011, 09:52 PM
Disturbed said i may run into other problems what kind as for my box im gonna have mobile enclosures design one but im just trying to think of ways I can do it

Louisiana_CRX
10-28-2011, 09:55 PM
what kind of 10's do you have and what vehicle are you running these in ?

brooklynjoy2008
10-28-2011, 09:58 PM
my max dimensions are 38*15*25 i will need 6cf so that leaves 2+ cf for speakers and such

brooklynjoy2008
10-28-2011, 09:59 PM
Re audio se 10d4 in a 2000 alero

Louisiana_CRX
10-28-2011, 10:09 PM
Re audio se 10d4 in a 2000 alero

you already have the 5 subs ? also which amp....

wenn_du_weinst
10-28-2011, 10:10 PM
you won;t fit that box through the opening, my grand am wouldn't fit one that big.

brooklynjoy2008
10-28-2011, 10:17 PM
I am building the box in trunk

brooklynjoy2008
10-28-2011, 10:23 PM
No i dont have subs or amp yet i want to figure out what i am gonna run first

Louisiana_CRX
10-28-2011, 10:28 PM
id do two upper series 12's if you want to fit the most in your trunk...4 of the right 8's would be killer also but not re8's

brooklynjoy2008
10-28-2011, 10:30 PM
So is cone area not important cause i was gonna go with 3 12s but 5 10s has more cone area

Haunz
10-28-2011, 10:33 PM
The placement of the subs will affect loading.. but for the subs to actually 'cancel' each other the distance between them would have to approach 1/2 the wavelength of the frequencies being played.. you can do the math if you like, but for subbass frequencies in the trunk of a car, it's a non issue..

NoLoud4U
10-28-2011, 10:33 PM
Cone area is important but so is power and airspace. 5 sufficated 10s will get walked on by 2 straight high powered 12s

Louisiana_CRX
10-28-2011, 10:35 PM
So is cone area not important cause i was gonna go with 3 12s but 5 10s has more cone area

12's usually need at least 2 cu ft plus port...10s about 1.5 plus port ...8's about 1 cu ft plus port in general....unless your going sealed cone areas not that important...not as much as speaker quality and proper box design...ive beat many systems in loudness with 4 8's that were running 4 15's...plus mine hit low as well....

slvrado28z
10-28-2011, 10:41 PM
put a 18" or maybee 2 15s.....but 2 12s would prob be the best with only 6 cubes

brooklynjoy2008
10-28-2011, 10:49 PM
Ok thanks guys so 2 12s and i will have a 70 amp fuse i know it depends on alot but could i burp 4000 rms on that fuse or what will i get out of it again i know it depends on alot but assuming my electrical is all sound

NoLoud4U
10-28-2011, 10:51 PM
I burp 2500 rms on a 70 amp. It pops it sometimes

brooklynjoy2008
10-28-2011, 10:51 PM
I thought about a 18 lol

slvrado28z
10-28-2011, 10:54 PM
get a bad *** 18 or 2 bad *** 12s....and what kind of amp?

brooklynjoy2008
10-28-2011, 11:04 PM
I was thinking of a brz 2400 or 2 it depends on how much i can use to compete

slvrado28z
10-28-2011, 11:11 PM
ive never used brz but i have a bxi2610 and im happy with it....i think you should get one of those and 2 12s

brooklynjoy2008
10-28-2011, 11:26 PM
You think 2 12s would be better than 1 18? I was wanting to do something different

slvrado28z
10-28-2011, 11:35 PM
i think 1 18 would be better

NoLoud4U
10-28-2011, 11:38 PM
1 18 will be a tight fit. I think 2 12s in a trunk wall will be hot

Louisiana_CRX
10-28-2011, 11:38 PM
im selling a couple nice 18's

slvrado28z
10-28-2011, 11:47 PM
1 18 will be a tight fit. I think 2 12s in a trunk wall will be hot

yeah that would be nice

brooklynjoy2008
10-28-2011, 11:48 PM
what is a trunk wall?

NoLoud4U
10-29-2011, 12:23 AM
it when you make a airtight wall out of the opening where your seat folds down or comes out. You are going to compete but you dont know what a trunk wall is?

brooklynjoy2008
10-29-2011, 12:53 AM
I just decided to compete up till now I have only had very limited experience with car audio pretty much I can hook up an amp and subs but in the last month i have done over 100 hours of research so i am learninf alot quick

NoLoud4U
10-29-2011, 12:57 AM
Keep learning.

hispls
10-29-2011, 01:34 AM
More DC lvl 5 10 Fun - YouTube (http://www.youtube.com/watch?v=Fqiz05ItWgE&feature=related)

^^^

this is how you get a trunk LOUD. I believe this is an old video and he runs a smaller flared round port these days, but you get the idea. Pair of 10's, perhaps pair of 12's, or a single 15. Another guy I know does right around 150 with a single 15 in a similar style setup.... does that at 42hz and it actually sounds pretty decent. 18's just don't work in a trunk

brooklynjoy2008
10-29-2011, 02:41 AM
ok so after some youtube I would love to do this with 2 12s but I was wanting to compete in the ameteur division and foam or caulks are not permitted.

brooklynjoy2008
10-29-2011, 03:19 AM
well after a couple minutes to think it over I will competing in the street class so now the fun begins, I know what I want and its time to build well plan to build. I just pulled my seats and all out to deaden my car and was thinking if this was the best setup for me and posted this thread to get opinions and now again it has changed but this is definitely what I will be building so I need 2 good 12s for this type of setup. Again I will be using a 70 amp fuse 18" from the amp from what I gather thats around 2500 watts.

disturbed471985
10-29-2011, 05:09 AM
Two 12's seems to be your best bet but I got tired of seeing the same ole 2 sub setup so I am going with three 8's subs back port threw the rear deck. Let us know which way u go and how it turns out..

StevesCarAudio
11-11-2011, 07:19 AM
A fuse doesn't blow based on wattage, but amperage. And different amplifiers draw different amounts of amperage to make the same power (all about efficiency). My MMATS amp (considered VERY efficient) draws up to 100amps to make 1600rms/3200ish peak. And thats in a car with 2 $1000 batteries and good 1/0 gauge wire and a H.O alternator.

Again fusing isn't going to determine your power. Hifonics BRZ1200 uses 2 70amp fuses (140 amps) to output 1200 watts. Don't worry about fuses until you have your amps so you know what to put on it. More important is running some good 1/0 gauge wire.

Phoenix Risen
11-11-2011, 08:52 AM
in meca the things people can do with small fuses is crazy. one of the crx's around here is burping a 150.4 consistently with only a 3 amp fuse, (granted these are not the normal 3 amp fuses) but they are stamped 3 amp in the metal and are legal. to really get loud in meca its actually more about efficiency than it is brute force, as i found out the hard way. it takes a lot of tuning and testing, building multiple enclosures to figure out the proper layout for the car, and there really is no right or wrong way to do things. (of course some ways can be easier than others).

brooklynjoy2008
11-11-2011, 01:47 PM
I will be using a rf t2000bd1, I have a power bastards 220a alt on the way, 2 batcap 2000, a 1/0 rf wiring kit, and will be doing my 1/0 big 3 in the next couple days. I have already used 100sf of deadening material and need to get more to do the head liner and finish that up but its coming along slowly but surley.

StevesCarAudio
11-11-2011, 06:36 PM
Is that the only amp you can get? RF T series amps aren't the most efficient, they draw huge amounts of amperage. If you had a choice maybe you could find a more efficient amp in the classified section. There are amps that draw a lot less power to create the same wattage as a RF t2000.

brooklynjoy2008
11-11-2011, 09:34 PM
Well that ***** the amp is on its way so thats what im using for now. I should have asked before i bought so how bad are they? Should I try to sell it and get another one? This is what happens when you dont do your homework! Earmuffs FK,SHT,DAM ok Im done. Well I may have a rf 2000 for sale soon if anyone is looking.

StevesCarAudio
11-12-2011, 04:05 AM
Basically a MMATS amp or any of the other more efficient amps will pull half or a little more than half the amperage of the rf t2000. Basically my MMATS amp at 2000 watts is pulling around 90-100 amps (100 amp fuse on it blows if it were to try and use more). My rf t1500 used a 250amp fuse. Can't remember the exact fusing for the t2000. If you are going for a setup that has to be super efficient that is not the amp that you want.

The rf t2000 is going to need at least a 250amp fuse on the power line. a 60amp would be toast a very low wattage output. Not to mention the t2000 was one of there older series amps, which were even less efficient than the current T series amps (which are not efficient anyways!) When I had my rockford t2500-bdcp, which was there new model which is alot more efficient than the older t2000, I had 3 kinetic 1800's, a 200 amp alternator and all Stinger high end 1/0 gauge and I still was getting a lot of voltage drop (3+ volts when at moderate to high volumes) we figured at the shop that it had to be pulling in excess of 350 amps peak 200+ continual when I was listening. Rockfords Power series amplifiers are absolute Amperage hogs. They take all you can give it and more. Given it may work with your set up (will need a 250 amp fuse not a 60) but even with that set up I think you would still be seeing some serious voltage drop and headlight dimming.

If you don't care about efficiency and have the electrical to back it up, the amp will work fine for you. Didn't know if you were competing somewhere where there was a limit on the max fuse size you could have, if so this is most certainly not the amp you would want (or any of rf power series). But don't get me wrong they are decent amps, they just require tons of power.

StevesCarAudio
11-12-2011, 04:11 AM
Yeah I just checked Rockfords forum and many people state the t2500 pulls in excess of 277amps at lower wattage and can go over 325 to do 3krms. and the t2000 seems to do about 250+/- a little. Haven't spent much time researching but that seems about right (I have tons of experience running RF amps)

It will be a decent amp, you may want to get something else if you were looking for something that didn't draw huge amounts of current. The guy I worked with used to test bench a lot of the amps we sold to see what kind of power they were pulling. I can bounce some questions off him if you want me to.

StevesCarAudio
11-12-2011, 04:16 AM
If you were going to be doing meca and had to be efficient your best bet would be to sell and get something different. If you just want something to power the subs and dont care about current draw, the rf t2000 will work fine. feel free to PM me or post on here and I can help ya out. I'm super tired and have to hit the sack.

brooklynjoy2008
11-12-2011, 11:34 AM
Thanks for your help and yeah i want to compete and have a 80a fuse 18" from amp. I will look for something else but this will have to work for now.

Canaan
11-12-2011, 12:07 PM
If I fire 3 10s front and 2 back with ports back will they cancel each other out? Its in the trunk of a 2000 alero and I was just wondering if this was practical or if they would cancel each other out?

2dr or 4dr alero?

If 4-door, try 2-12. Subs on passenger side, port drivers, both firing into the cabin. ~4cuft, the cabin will like to peak ~56hz.
I did 151+ w/ 2 DD2510's in a build for a co-workers Alero, and that was without sealing the trunk off.

brooklynjoy2008
11-12-2011, 12:18 PM
2dr or 4dr alero?

If 4-door, try 2-12. Subs on passenger side, port drivers, both firing into the cabin. ~4cuft, the cabin will like to peak ~56hz.
I did 151+ w/ 2 DD2510's in a build for a co-workers Alero, and that was without sealing the trunk off.

I have been trying to find someone that has used a 4dr alero! I will be using 1 15" trunkwall, cabin peaks at ~51hz. if I can get the funds up before they are gone I will grab a 15" fi btl n3. As for sub and port placing thanks I didnt want to have to do a bunch of rebuilding to find the optimal setup. If I tune that high though as a daily I will lose all of my low end can I change ports has anyone ever done that?

StevesCarAudio
11-12-2011, 10:08 PM
Good luck with that 80a fuse on the amp! post when you see how it works, I am curious to see how much power you cant get out of it before it blows an 80a.

NoLoud4U
11-12-2011, 10:23 PM
Its about heating up the fuse. You will be fine burping a 60 on that RF. I burp a 70 on my ZX2500. I can also Park and pound a 70 most of the time, more good then popped. Cheap generic fuses are your freind. Mini anl and AGU fuses. You can also run them in line. 2 35 amps. MMATS are very good with the fuse format though. There is a 4K running 60s around here

StevesCarAudio
11-15-2011, 03:56 AM
Idk, I toated a 125a with the rf t2000 with a friend in his car. It had great electrical too. I was running it hard... but still. We had 3 batteries in that car, a 250amp alternator, all kicker 1/0 all around and for the big 3. It had a big Shuriken 1800 battery up front too, in addition to the 3 kinetik 2000's.'
I did'nt really look his electrical over, but he knows his stuff it should have all been perfect, the older rockfords just really pull the juice. Unless there is a trick to running smaller fuses. or crap fuses that don't actually blow when they should...

brooklynjoy2008
11-15-2011, 04:13 AM
The new t2500 amps r only 65% efficient at one ohm so the older ones r alittle worse i would assume. But even at 65% @13.8v thats 223a for 2000w and 279a at 2500w so im gonna look for another to compete with, since its all about being as efficient as possible.

StevesCarAudio
11-26-2011, 01:16 AM
If you decide to sell the t2000 let me know, I may be interested in it. Need a amp for my new project that I will be starting soon

---------- Post added at 11:16 PM ---------- Previous post was at 11:15 PM ----------

If you are looking for an efficient amp, I have a mmats amp I would trade as well. It's going to be extra soon, need more POWER!!! its a never ending cycle

NoLoud4U
11-26-2011, 02:23 AM
You have to keep it clean also. I would blow fuses quick before I set the amps up with a dd1

Phoenix Risen
11-28-2011, 11:38 AM
the cheap crappy fuses are your friends. mainly for the fact that they will take more than what they say they will. especially for short periods of time. for burps you only need the fuse to hold out 3 seconds. last season i was burping my mmats 4000.1 wired at .5 on 2 40 amp fuses. (couldnt quite get the full potential out of it though)

and you dont always need to draw every last watt out of an amp to compete. everything depends on the setup though.

Phoenix Risen
11-28-2011, 11:39 AM
dbl