KCTYPHOON

before anyone reads this, i would just like to politely ask that no one responds to this question unless they are absloutely sure of the answer. this little stereo hobby is expensive enough and i'd like to aviod having to invest even more money to do things twice, half-assed, or just entirely wrong by going on what someone "thinks" rather than getting the advice from some one that "knows" through extensive car audio experience. thank you..
ok.. here goes.. i have a 95 maxima, so far my system consists of a double din jvc receiver ( i know.. but its already in there), 2 sets of daimond audoi 6.5" inch component sets that are powered by a fosgate 600a4, four 10" pheonix gold x-max's (sealed box) powered by an fosgate 1100a2, and a kenwood 6 disk changer. i have an optima yellow top battery, stock altenator (spelling?), 4 gauge power and ground wires that run to distribution blocks in the trunk that are then downsized to what i belive is 8 gauge to goto the amps. the power wire is protected by a 75 amp circuit breaker about 2 feet away from the battery. there is a stiffening cap in line with the 1100a2, its an older mtx model that i just had laying around. in a previous post i had explained the problem i had with the 1100 overheating and burning up the gound at the connector. it will be getting fixed shortly and i was planning on putting that one back in along with another 1100a2 that i have to power the four 10's. down the line (if i ever make it to this point) i have another diamond audio 6.5" set that i wanted to put in the kick panels and probably upgrade that amp also from a 600a4 to mabye an 800 or so... whos knows... i might (probably) not ever do this, but it would be nice if i could. anyway.. the question is.. what EXACTLY should i be changing in my set-up to power these 2 1100's with the 600/800 to avoid any problems with overheating or power supply? i figure i have to at least upgrade the gauge of the power wires to 2 or even 0 gauge? i also think i sould invest in "the cap" for stiffening. am i on the rite track here? i would seriously like to aviod having to change altenators or getting a second battery. is that just like totally unavoidable for what im asking of this stock altenator and this stereo i would like to persue?? i know i might be getting a bit crazy here but i would really like to know what i should be doing to power all this and not have any problems before i goto the stereo place where this guy is just gonna see me as one big dollar sign. PLEASE!!!! PROFESSIONAL ADVICE ONLY... what do i need to do here?????

jashick

Can you give more info:
how are the 4 subs wired in the box?
Are you running the amp mono (bridged) or
stereo (2 channel)? How high did you set the gain?
Also, when you get your amp fixed, ask for a specific diagnosis.

SWEETSOUND2001

iTrader: (30)

Before you go and drop some serious moolah on unneccassary mods do the following:
upgrade all the power leads under the hood to at least 4ga or 2ga even better. This includes battery to chassis, alternator to chassis, alternator to battery, etc. Think of it as pressure in a water hose....
Also, if you are burining up ground, which i can't imagine why, maybe you should ground the amps with 4 gauge wire.
Another thing: are the grounds for the amps really grounds? Try with an ohmmeter and see. They should be connected to the actual frame of the car.
Amps heating up could be a number of things such as bad connections/grounds/not enough power? someone please correct me on that if im wrong. Or maybe youre running too low of an impedance, and another thing is RF amps are known to run hot from what i hear.
As far as speakers go, i would take out the speakers from the doors and get some nice kick panels built for them. Makes a world of difference, i can attest to that.

Good luck and let us know what happens.

Anton

CanuckAMP

So far everyone's pretty much given great advise. One thing I'd like to add is that you will not notice the use of a capacitor on the amps for your front stage. The amount of bass that they will play and hence the amount of current they will draw from the electrical system won't make it cost effective to put capacirtos on them. Concentrate adding the caps to only the subwoofer amplifier(s).

How long are your ground wires from the amp that's buring up? If they are grounded more than 18" away from the amp's location you should shorten that length by picking another spot to ground your amp. Also gojng with 4G grounds wouldn't be a bad idea either.

If you play the system with the engine off for fairly long periods of time at high volume you should consider adding a second battery. If you don't it's not necessary.

The stock Nissan 90A alternator will probably work out fine for the upgrade to higher power amps for the front but if you add a second sub amp you should be looking at an upgrade to either a high output alternator or at least get a rewound unit with a few extra turns for more power delivery.

Now as for adding a second sub amplifier you should carefully consider your wiring options for the subs you have. The PG Xmax are 4 Ohm subs and I assume you either have them wired up in 2 Ohm stereo or 4 Ohm bridged to your 1100a2. If you add a second 1100a2 how will you be wiring your subs? Those amps are not stable into a 2 Ohm bridged load so you can't bridge 2 subs per amp. You would be left with either 4 Ohm stereo wiring for each pair of subs per amplifier giving you 250Wrms per sub. Right now you are giving each sub about 250Wrms (prolly more based on the RF birthsheet) in your wiring setups (1000W / 4 subs). In essence you would be adding a second amplifier and not getting any more output out of your system. Due to the ineficiency of amplifiers though you will be increasing the current demand with a second sub amp installed without the benefit of more power....

The Alumapro "CAP" is really not required in your case. You really won't notice a benefit from it on your setup. one 1F cap per 1000W amplifier is sufficient stiffening. If you are going to add the "CAP" for esthetic or install related reasons then that's another matter entirely.

If you want amplifier upgrades I'd consider a Class D amp for your install that will allow you to run your subs into a lower load and benefit from more power.

Whitemax

I'd give my advice but then I'd just be repeting everyone else
(spam)

KCTYPHOON

if i ever make it to the piont of adding the second 1100a2 how do u suggest i wire the subs? i am the worst bass head you could imagine.. whats the best setup i can go with??

KCTYPHOON

before i forget.. just wanted to thank everyone for reading my post and offering advice.

CanuckAMP

Well if I were you I wouldn't add another 1100a2, for the very reason that I mentioned above. You cannot wire them up to 4 subs to get any more output than you currently have. Unless you get 4 different subs.

Your wiring options with a pair of 1100a2's are only in stereo per pair of subs on each amp for a 4 Ohm stereo load or in bridged mode with each sub wired up in series for an 8 Ohm load. Doing either will still result in 250Wrms gooing to each subwoofer. In your current setup you already have 250Wrms going to each subwoofer. RF stereo amps are not stable to under 4 Ohms in bridged mode. If you tried to run your subs in parallel per amp that would create a 2 Ohm load and the amplifier will draw alot of current trying to drive the 2 Ohm bridged load. It will overheat and either shut down on a thermal overload or blow a fuse.

Your safest bet for upgrading power using the same subs is to get a Class D or high current amplifier that can produce more power than a single 1100a2 when bridged into a 1 Ohm load.