Help with car audio system please

Thread Starter

Nathan_

Joined Dec 19, 2013
1
Hey there.

I have a 08 chevy trailblazer. Ill be installing a mtx td1000.d amp 1000rms, will be wiring (2) JBL gt5-15 15' subs rated at 300rms svc 4ohm, will be wiring to get 600rms at 2ohm. also have 4 lightning audio 6.75' 3-way full range 40rms 4 ohm door speaker (need help matching an amp)

My main concern is if the trucks stock battery and alternator will be able to handle the load. Any advice would be AWESOME
 

monster_catfish

Joined Mar 17, 2011
116
Personally, I intend to keep buying more giant speakers and amplifiers until motorists ten blocks away are able to hear and feel in their bones the seismic bass notes from my Sex Pistols CD collection, played full blast from my parked Ford Pinto, whose bald tires I really should get around to replacing some day.
 

praondevou

Joined Jul 9, 2011
2,942
A very approximate calculation:

1000W at 12V with about 80% amp efficiency gives about 100A. That's why they recommend 100A inline fuse or circuit breaker in the manual. 100A is a LOT.

I don't know if your alternator is able to provide such power at various rpms. Try it out. You can also install a high power alternator replacement: http://www.powerbastards.com/proddetail.asp?prod=8498-250

You will need earplugs for 1000W inside your car.

If someone asks you to turn down the volume then do it.
 

bountyhunter

Joined Sep 7, 2009
2,512
Hey there.

I have a 08 chevy trailblazer. Ill be installing a mtx td1000.d amp 1000rms, will be wiring (2) JBL gt5-15 15' subs rated at 300rms svc 4ohm, will be wiring to get 600rms at 2ohm. also have 4 lightning audio 6.75' 3-way full range 40rms 4 ohm door speaker (need help matching an amp)

My main concern is if the trucks stock battery and alternator will be able to handle the load. Any advice would be AWESOME
Buy some ear plugs.

I don't understand this:

will be wiring to get 600rms at 2ohm
Do you mean you think you will be getting 600 WATTS RMS?

In reality, an average power level of about 10W will blow the windows out of the car.

I think you mean the subs will be wired in parallel?

If so, check and make sure the amps are rated to work into a 2 Ohm load. Some won't handle that low. Their current limit circuits may start firing on high peaks.
 

bountyhunter

Joined Sep 7, 2009
2,512
Personally, I intend to keep buying more giant speakers and amplifiers until motorists ten blocks away are able to hear and feel in their bones the seismic bass notes from my Sex Pistols CD collection, played full blast from my parked Ford Pinto, whose bald tires I really should get around to replacing some day.
The rule of thumb I go by is that I have enough power when I can put on rap music and the ground vibrations knock the paintings off the walls in the house across the street.
 

bountyhunter

Joined Sep 7, 2009
2,512
A very approximate calculation:

1000W at 12V with about 80% amp efficiency gives about 100A. That's why they recommend 100A inline fuse or circuit breaker in the manual. 100A is a LOT.
Most people have no "feel" for what average power an amp really needs to make very loud music. As I said above, if the average power exceeds about 10W RMS, I doubt you could stand to be in the car. The massive power amps do put out the high peaks that subs need to shake the ground, but average power should probably never exceed maybe 20 - 30 Watts if that.

That's the reason people typically install the monster capacitors (one Farad or more) near the power amps so they can have a charge source to deliver the high peak currents.
 

praondevou

Joined Jul 9, 2011
2,942
20W may be enough if you want to listen to loud music. It's not enough if you want to be heard a few blocks away. That's what they want. I've also seen a "test" on youtube where they put so much power out of the speakers that the windshield breaks and simply falls apart.

I hate these boom cars when they are in my neighborhood. I like the description of the urban dictionary: "A vehicle containing a belligerent stereo system with subwoofers that render the trunk useless and broadcast low frequencies for hundreds of yards"

Anyways, when I was young I also thought everybody would be impressed by loud music I was playing in my car. Guess there were not... :rolleyes:
 

wayneh

Joined Sep 9, 2010
17,498
These discussions always remind me of :

The Hitch Hiker's Guide to the Galaxy notes that Disaster Area, a plutonium rock band from the Gagrakacka Mind Zones, are generally held to be not only the loudest rock band in the Galaxy, but in fact the loudest noise of any kind at all. Regular concert-goers judge that the best sound balance is usually to be heard from within large concrete bunkers some thirty-seven miles from the stage, whilst the musicians themselves play their instruments by remote control from within a heavily insulated spaceship which stays in orbit around the planet - or more frequently around a completely different planet.

Their songs are on the whole very simple and mostly follow the familiar theme of boy-being meets girl-being beneath a silvery moon, which then explodes for no adequately explored reason.

Many worlds have now banned their act altogether, sometimes for artistic reasons, but most commonly because the band's public address system contravenes local strategic arms limitation treaties.

This has not, however, stopped their earnings from pushing back the boundaries of pure hypermathematics, and their chief research accountant has recently been appointed Professor of Neomathematics at the University of Maximegalon, in recognition of both his General and Special Theories of Disaster Area Tax Returns, in which he proves that the whole fabric of the space-time continuum is not merely curved, it is in fact totally bent.
 

praondevou

Joined Jul 9, 2011
2,942
These discussions always remind me of :

The Hitch Hiker's Guide to the Galaxy notes that Disaster Area, a plutonium rock band from the Gagrakacka Mind Zones, are generally held to be not only the loudest rock band in the Galaxy, but in fact the loudest noise of any kind at all. Regular concert-goers judge that the best sound balance is usually to be heard from within large concrete bunkers some thirty-seven miles from the stage, whilst the musicians themselves play their instruments by remote control from within a heavily insulated spaceship which stays in orbit around the planet - or more frequently around a completely different planet.

Their songs are on the whole very simple and mostly follow the familiar theme of boy-being meets girl-being beneath a silvery moon, which then explodes for no adequately explored reason.

Many worlds have now banned their act altogether, sometimes for artistic reasons, but most commonly because the band's public address system contravenes local strategic arms limitation treaties.

This has not, however, stopped their earnings from pushing back the boundaries of pure hypermathematics, and their chief research accountant has recently been appointed Professor of Neomathematics at the University of Maximegalon, in recognition of both his General and Special Theories of Disaster Area Tax Returns, in which he proves that the whole fabric of the space-time continuum is not merely curved, it is in fact totally bent.
Douglas gone so early was really a loss.
 

BobTPH

Joined Jun 5, 2013
9,003
The boom cars have now been supplanted by crowds in football stadiums as the loudest and stupidest thing in the universe. They are actually handing out earplugs at the gates to NFL games.

Bob
 

tcmtech

Joined Nov 4, 2013
2,867
Cheap vehicles with huge sound systems are nothing new. I was running around in the early 90's with a system that was pushing 1000 W RMS back then.

Being heard a few blocks away is childs play.:rolleyes:

I was well known for being heard a mile out of my local small town and two miles plus on the open flat prairie! :p

BTW despite concerns about hearing I am 39 now and I still test above average for sensitivity and range and I am still known to turn it up and rock out now and then despite my wifes continual protests that I will go deaf. :D
 

gootee

Joined Apr 24, 2007
447
Most alternators, even the 250-amp ones, will not produce more than 40 to 60 amps, when the engine is idling. If you might be idling for a long time while drawing high current, that could be a problem because your battery could discharge too much and its voltage could drop to dangerously-low levels.

There are at least three possible mitigation strategies, after making sure that you have the best-possible battery, and a large-enough alternator. One is to use a smaller pulley on the alternator, so it will turn faster at idle speed. The second one is to see if the vehicle manufacturer offers a dual-alternator kit. Some do. The third is to install a second battery, to help supply current when idling.

I would try it with your vehicle as-is, at first, and if none of the wiring melts but the battery dies or fries after idling with high volume, then try the possible fixes. I would probably try using two batteries, first.
 

bountyhunter

Joined Sep 7, 2009
2,512
Cop cars which have a lot of current demand from lights used to have a high output alternator and a second battery. With new LED lights, maybe not necessary but that's how they used to do it.
 

BillB3857

Joined Feb 28, 2009
2,571
With that wattage, you'll pop the spot welds on your trail blazer's body! Must be trying to make up for shortcomings in other areas.
 

trader007

Joined Feb 27, 2010
249
i say get a larger alternator op, it never really hurts to do so. any stock alternator is **** poor for running a subwoofer system, the overhead they have to begin with is only 20% or so when all your a/c and everything is on.

have fun too. dont listen to these old farts, if you can afford it and you want it just do it. you won't get to do it forever, life always takes the subwoofers away somehow...
 

trader007

Joined Feb 27, 2010
249
No, it takes away the high frequency hearing. I can hear subwoofers just fine; I just cant hear anything above about 2kHz.
that would be dreadful... some of my favorite moments are listening to flac files on my hifi stereo...

i guess im glad i never had more then 1000w pushing my sub...

i do have a high pitched ring in my ears all the time... like that noise you hear when turning on an old crusty tube tv. i just figure it means i myself is still "on".
 
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