4runner4life2

jgrimball
hey whats going on i have a brand new amp for sale if your interested. it should be exactly what your looking for its a Rockford Fosgate 401s 1200 watt 2 channel amp. It is brand new and in the shrink wrap that it came in still. I got it for a christmas presents to power my two 12 inch mtx thunder 6000 subs. the subs are new too and are also for sale. i decided not to put the subs and amp in because i just didnt need that intense of a system and instead i put a new sony xplod faceplate on and added some 6 x 9 speakers to the back and it sonds awesome. so if your interested ( or anyone else) i will probably make a thread in the for sale section but the BRAND NEW SUBS in a box and NEW AMP are for sale.
duno if your interested but its a sweet system
sorry for sounding like a salesman :pat:

edit: send me a pm or email if your interested

User 051420

Eric!
Thank's a million for making that diagram! It saved me about 25 millions words!

Bridging an amp, makes the amp put all of its power through one channel, and since two 4 ohm subs wired together appear to be 2 ohms to the amp (2 ohms is twice as hard to push as 4 ohms, but effictively doubles the power). So when you make the amp push a 2 ohm load, it works twice as hard and produces twice the power, and each sub shares that equally (hopefully).

This is so hard to explain, I probably only repeated myself twice- I think you should understand though.

Google "subwoofer wiring", and you should understand this perfectly.

Pleast note: Your amp will have to work twice as hard to power these subs now, and may get very hot. It should be stable enough to run at 2 ohms because it is a quality amp. However, it may cut out if you push it hard for a long time.

Best of luck!

dexter

Why o why do so many shops wire subs like that??? WHY? when i got my first system done it was like that, my friends suburban same deal, x girlfriends honda same, friends pathifnder same, 2 friends 4runners same f'n deal. and they were all 2ohm stable amps with middle to top of the line subs/amps. it confuses me soooo much. argggg

glad you got that figured out quick.

User 051420

Some lower end shops do it that way beacuse they dont know any better, and dont really care about pushing the system to the max. Whats totally ironic, is that UNDERpowering a sub is worse than OVERpoweing it. Essentially, they wired it for failure; possibly to get you to buy new stuff:pat:

It seems that they had one of his subs running in reverse phase (super odd).

JGrimball

2 more questions:

1) I saw a subbox on the internet that has like pillow stuffing
material in the box behind the subs. What is that for?
Should I do that?

2)What should I dynomat to keep out some rattle?
The most ratttle heard is when standing outside the car
and it comes from the rear.

Thanks!!!!!!

gn86r

is that amp a mtx 250x? i dont thing that amp is stable into 2ohms bridged. might wanna check before you fry that amp.

tenfourtyeight

When I first installed subs in my Jag, the trunk rattled like hell, so I went to Kragen and got some grey foam weatherstripping with a sticky back, and lined all of the places where metal touched metal. It took a few rounds of opening and closing and bending over to listen to find out where the rattles were exactly, but it only took about 10 min., no more rattle.

ruizs

Also, if you can, you should separate the power and speaker wires (i.e. cut the zip ties, and run them on diff. sides of the car). When there's a lot of current flowing in the power wires, it can induce a current in the speaker wire. By separating the cables, you can get cleaner sound. Not too bad, better sound by just moving cables (read 'free')

JGrimball

This may be dumb but....

I know you cant tell me cause you not here to listen
but give me some guidlines on how I should set the:
GAIN, EQ and FREQ.


gn86r:
YES it is a MTX 250x.
What would be the worst that could happen?

User 051420

Hello!
If your amp wasn't stable to 2 ohms, it would simply kick off into "protection mode" after running it hard for a little bit. Test it!

Also, to set your gain, turn your system up the loudest you will play it, and then slowly raise the gain until you hear any distortion, then back off until it stops. This "syncs" the head unit and the amp.

The other settings should be already set fine.

A work about Dynamat. If you want to stop the exterior rattles, Dyanmat WILL NOT help. No vibration dampening product will stop the exterior rattles. It sucks, I know. The idea posted earlier about the weather strpping does work though! Buy it, and paste it liberally. For your licence plate, dry backing that with sticky foam. IF that doesn't work, Dynamat sells a licence plate kit which works very well.

Hope you dig your system now that it's wired properly!

Eric

you are only partially correct. you should seperate your power wires and your LOW VOLTAGE signal wires, i.e. your RCA jacks. Speaker wires have much less problems with noise. plus it's harder to hear noise in a subwoofer setup, especially for a noob sound guy (no offense to jgrimball, but the car is not going to win any IASCA events)


jgrimball - the pillow stuffing is called poly-fill, what it does is slow down the sound waves, this tricks the sub into thinking it is in a larger box. The end result is the subs will play deeper, lower, and a little bit louder. A bag of polyfill will usually run $2-3 so it's a good cheap investment. You must make sure it's polyfill though becuae any old stuffing wont work, this stuff works best.

as far as dynomat, you should dynomat everything that rattles. get rid of liscense plate frames, and dynomat the back of the liscense plate. those are biggies. then just start pushing on pannels and see if the rattle goes away. once you find a spot, remove the pannel, and dynomat the metal. Using a foam sealer like somebody else mentioned also helps stop rattles

settings -

FREQ - for a sub, somewhere around 80hz is pretty normal

EQ - I'm thinking this is some kind of bass boost (never played w/ MTX amps) set it 1/2 way up or less, unless you want that ghetto bass, the crank it up. over 1/2 way usually introduces more distortion than neccessary

GAIN - this setting is usually always set wrong, so it will be a couple of steps

first set your headunit to the MAX level you want to listen to. this is usually never over 3/4 the way up on the headunit. over 3/4 the deck will distort really bad. do this with the sub gain all the way DOWN

Once you get the deck as loud as you are comfterable listening, adjust the gain UP until the sub starts to distort, bottom out, or just plain sound like crap.

After you get the sub to it's limits, quickly back the amp down a bit since it isn't really good to have a sub playing at it's limits.

this is usually easier if you have a buddy adjusting the gain, and you listening to the sub, or sitting in the drivers seat.


If at any time the amp starts to clip, shut off, or sound terrible, tunr the volume down and investigate the problem. If you cannot figure it out take it to either the shop that did the work, or another shop that might be more capable of fixing the system.

Just have to ask, did you buy this stff at circut city?

JGrimball

YES I did buy at Circuit City.
Anyway....
Is it safe to stuff the sub box with the poly-fil?


What rattles the most is my gasdoor and my windshiel wiper.

User 051420

The sticky weatherstriping will fix the gasdoor, it did on mine. PLEASE PLEASE PLEASE let me know if you find a way to stop the wiper from rattleing. I'm thinking of maybe getting an all weather solid rubber wiper.

Memphis_Yota

hey jgrimball
to your questions...all the stuffing is doing is making your subs think that the box they are in is acually bigger which will give you a deeper sound in the bass...soo if you listen to low low bass and go into alot of SPL competitions then you need a bigger box or if youhave limited room then you can stuff them...but first of all i need to know what kind of box you have such as ported or sealed and bandpass..and the measurements of the box then tell me what kind of music you listen to most and i can tell you what you want for your box...
and for your next question...just to let you know...dynomatt is really expensive and it takes awhile to put it in properly...but what you wanna do is find a song that has alot of bass and play it...then listen in your truck for all the rattles and make a note of them..then go outside and find out were the body panels are flexing and rattling the most...these are the points that you want to work on the most...so what you do is you strip off all the plastic and put the dynomatt and the bare metal...all it does is it helps stop vibration...it deadens sound...and everything that shakes or rattles takes away from the sound of your bass...its basic physics...its all resistence....
if anymore questions or need help then keep me posted
Cody

Eric

99% of the time poly-fill will make some kind of improvement in the sound

how did the wire switch and tunning go?

JGrimball

Well after re-wiring the amp the correct way, I has a LOT more bass. It was really overpowering. Then later after I recieved more
info from you guys. I filled the box with poly-fil and adjusted my amp and

I now have deep low bass that isnt overpowering the music.
When I listen to rock it has a good sound and when I listen
to hiphop I can hear the words but also feel the low bass hits.

Thanks to everyone for you combined help in solving this
issue. You also saved me from buying a new amp.

Memphis_Yota

Hey kgrimball
another thing you can do is add a line driver to your system...all this does is goes between your deck and your amp via your RCA cables...and will give your amp more voltage coming from your deck which will give you a better output...and there not that expensive only around $140 and they give a big output...so try that if youy want or keep me posted for more questions
Cody

JGrimball

How much polyfil should I put it?
I read somewhere just a little bit. I put ALOT!!!

Tenkom

I have a single 10" infinity kappa sub in my truck and I am wondering what is the correct way to wire that into my alpine v12 amp. Its a 5 channel, so my 5th channel is for my sub, the channel is rated at 200 watts, my sub is rated for 50-275 rms, how do i get the most from my sub??

Thanks guys
ken

User 051420

You can't bridge a single channel, so what you have now is what you get. I'd recommend getting another amp if you really want more power.