Hi guys,
I recently purchased a JVC KS-AX4504 600W 4 channel amp which now powers my rear speakers and my sub. However I've been having a problem with it. It heats up abnormally and the red indicator light comes on when ever I connect my newer more powerful sub (1200W kenwood W3012) or when I turn the volume up when I have to amp on high settings. Now i read it says it could be wiring or the speaker's impedance's is not matched to the amp which they are and I did the wiring all correct so I'm stumped. Some1 help! Thanks..

It will be your wiring to the power and ground on your amp ( Should have at least 4 ga ) or the impedence wiring. If it is DVC it is most probably wired to 2 ohm and under

I bought 5 gauge ground cable (which is quite thick, could barely fit a wire crimp on it! Even the yellow one I used was really too small) for my amp and a 10 gauge power wire so maybe the power wire is too thin I'd say. For the time being I have my old sub back on it just so I actually have decent sound when I drive around cause when I crank it just a bit higher than usual with the new sub, it just cuts out completely unless I switch the car off then or I have the amp on basically no amplification. Should I try buying a new power wire before I try forking out more money which I don't have to buy another amp?

Couple of mistakes there :( In car audio the ground cable and power MUST always be the same size. Messes around with voltage drops otherwise. Although you are running a small amount of power i would still say that power cable is way to small. I would recommend 4 guage minimum. That would MOST LIKELY be causing the overheating as its not getting the power required to run properly

http://www.ryda.com.au/JVC-KS-AX4504-Car-Amplifier-p/ksax4504.htm

Looking at this is says you have 4 ga power inputs so i would be using those at least. What sort of fuse size does it take aswell? And what have you installed fuse wise?

Yeah I gotta a fuse on the wire. Dunno what size the fuse is tho man. It's a sony fuse that's all I kno. I might be able to take it apart and find out aye. So u reckon I should buy a 4 gauge wire as well bro?

Yep i would be buying that before you do anything else. And making sure the fuse at the battery is correct. That will be what is causing it

Alrighty man I'll take that fuse apart and find out all the details of it. I gotta a long weekend this weekend cause I got an RDO at work :D so I'll have plenty of time to do stuff on the car dis wkend. Thanks for all yr help aye. I'll let you kno of the outcome.

No worries man

First of all MR SPL you can use a small power wire with a larger ground it just cant be the other way around.

As for your protect issue looking at the amp specs if your are bridging 2 channels onto the one sub (which i presume you are) try just running one channel (eg: channel 3 OR 4 NOT BOTH) into the sub and if it works it means that you amp cannot product a 2ohm load when bridge.

I have the specs right here and it doesn't say anything about bridging it to 2ohm, so my guess is that its not stable.

Then you have 2 options, put your old sub back in OR run your new sub at 8ohm by following the diagram in the link below.
http://www.rockfordfosgate.com/rftech/woofer_wizard.asp?submitted=true&woofer_qty=1&woofer_imp=4

Even in the case though you'll be lucky to get 50w rms into it.

Also as for the fuse something around 150 give or take a little should be fine, for the inline engine bay fuse, but keeping in mind if the fuse is a low rated fuse and blows the amp will not go into protect, it will receive no power what so ever.

First of all MR SPL you can use a small power wire with a larger ground it just cant be the other way around.

As for your protect issue looking at the amp specs if your are bridging 2 channels onto the one sub (which i presume you are) try just running one channel (eg: channel 3 OR 4 NOT BOTH) into the sub and if it works it means that you amp cannot product a 2ohm load when bridge.

I have the specs right here and it doesn't say anything about bridging it to 2ohm, so my guess is that its not stable.

Then you have 2 options, put your old sub back in OR run your new sub at 8ohm by following the diagram in the link below.
http://www.rockfordfosgate.com/rftech/woofer_wizard.asp?submitted=true&woofer_qty=1&woofer_imp=4

Even in the case though you'll be lucky to get 50w rms into it.

You can but you shouldn't. Last time i checked the power and ground cable should be the same size. Thats the way it is supposed to be done on countless examples.

If it cuts out when you connect your sub its more then like the wrong independence on the subs side
If your bridging then its normally a 4ohm load at the amps end so you'll need to match it with the sub
Would also check the gains on the amps, lower the gains and see what happens
5ga power wire should be ok for starters, and the ground wire should either be the same size or bigger
Remember to keep the grounds short
If you havent got a main fuse in the engine bay then i would get onto it asap
To work out count up all the amps on the fuses on the amp, add alittle more then place fuse about that size

As for your protect issue looking at the amp specs if your are bridging 2 channels onto the one sub (which i presume you are)

Yeah I am bridging the two channels labelled "rear" for the sub on the amp. The cutting out thing also happens with the old sub if I have the amp settings high and I crank up the volume too. Do u reckon I could connect both subs to the two rear channels instead? Or just stick with the one on one unbridged channel?

You right when you say "You can, but shouldnt" MR SPL, its good practice to ensure they are the same size, but unfortunately some people do not know this so its easy to keep it simple for them, in the case the size of the wiring isnt an issue.

The cutting out thing also happens with the old sub if I have the amp settings high and I crank up the volume too. Do u reckon I could connect both subs to the two rear channels instead? Or just stick with the one on one unbridged channel?

If the gains high, the amp and sub are probably clipping or overheating.

As for trying one sub on one channel, go for it, its easier than us trying to trouble shoot something when you can try it.

Edit: What was the old sub was it a Dual 4Ohm Sub aswell? If so problem found. (maybe) lol.

The OP is running 10 GA power cable? How is that not an issue?

The OP is running 10 GA power cable? How is that not an issue?

My mistake I missread that part. I somehow thought he was running 8 gauge.

In the case run the sub bridged and then unbridged on the FRONT channels (you will need to disconnect the speakers for this) and then see what happens.

If power wire is the issue you shouldnt have an issue if you are only using 2 channels.

My mistake I missread that part. I somehow thought he was running 8 gauge.

In the case run the sub bridged and then unbridged on the FRONT channels (you will need to disconnect the speakers for this) and then see what happens.

If power wire is the issue you shouldnt have an issue if you are only using 2 channels.
Alright man I'll try that. The old sub is a kenwood KFC-W1012 800W. And yeah the subs do clip and overheat sometimes when I turn the gain up. You said my new one was a dual voice coil, I looked it up and it only appears to be a single voice coil (my old sub is also single).

http://www.crutchfield.com/S-sT1TfQT8tdf/p_113W3012/Kenwood-KFC-W3012.html

Your new sub is only a single voice coil so no problem there. Just try on one channel and see what happens. With the sub you have you shouldnt have any problem except for wiring. That is what im putting my money on however

Another mistake of my behalf, i didnt think the 3012's came in SVC, well thats much easier.

So now all you need to try is to run the sub off one or both of the front channels (in place of the speaker), and the reason behind that is, since you are running 10gauge wire you can really only run a max of 30amps and thats still not the best thing over a run of say 5 meters. How ever if you are only running the 1 channel you wont be drawing close to the 30 amps, max will be 25, and then you need to look at your findings and choose the best course of action.

Even in the case though you'll be lucky to get 50w rms into it.
Very lucky.

OP mate, you would be much better off just running the 4 channel to the speakers and a monoblock for the sub.
Speaking from experience here mate. Yes, it is more expensive and complicated, but it will be much louder, much clearer and more reliable.

Wonder what I can do with the other two channels then? And Will the sub clip or overheat with a monoblock? Also, if I wanted to have a second sub, could I just get a second two channel amp? And one more question, would it be better if I just had the one sub with the monoblock or getting two with a two channel? Thanks in advance

Wonder what I can do with the other two channels then? And Will the sub clip or overheat with a monoblock? Also, if I wanted to have a second sub, could I just get a second two channel amp? And one more question, would it be better if I just had the one sub with the monoblock or getting two with a two channel? Thanks in advance

Lets take it one step at a time, if you find running it off one channel works fine, then the next upgrade will be power supply. If you only plan on running this one amp 8gauge will suffice but if you think you may upgrade in the future best get some 4 gauge.

On a single channel it might sound crap and when there's bass coming out of the other speaker channel, the sub wont produce anything like those songs with the left right effects etc.. But what do u think of gettin a monoblock? Waste of time and money or a good idea?

Always a good idea mate :) Even a cheap one from my work.

http://www.jaycar.com.au/productView.asp?ID=AA0454&keywords=mono+block&form=KEYWORD

This one would be ideal but you WILL have to upgrade to 4 guage cable after that. At least then you will have a 2 amps for seperate applications

Wow shit mate thats a good amp from jaycar. Only $220 too! 500W RMS! Wow shit thats awesome bro can't buy it right now tho, I'll wait till nxt week's pay. I'm not gettin paid much as a first year apprentice glazier haha so I really have to save for stuff aye. What brand is that amp?

Thats alright mate. They are that price for the next few weeks. On special. I work at jaycar and these amps have prooved to be very very good bang for your buck. Never had a problem with any of mine. PM me mate and i might be able to do you a better deal on it ;) Amp is response which is jaycars brand. Like i said although not alpine there is no doubt these amps are worth their money :)

there is no doubt these amps are worth their money :)

Yeah for a brand like JVC, pioneer, kicker or kenwood etc with this sort of power u'd be paying at least $350+. Wonder if Jaycar Townsville (thats where I live) have any in stock? So have you had some good reports on them? Like are they still as good quality, as reliable and as powerful as the others?

Use the 4 channel in my car and my mate runs a mono block in his car. Which he has taken out a few sound comps with. Yet to have any problems with either of them and the one im running is 3 years old off the sound board. Still going strong lol Mainstream brands are overpriced because you pay for the brands. Simple as that

I would say they would have some in stock

Also the last test done on them they came out first against all those brands for rated output. Interesting i thought

I got a 4 gauge power wire today but it still does that stupid heating up and turning off shit. I sold my old sub and amp to a mate so I can't use that no more. I think I'll buy that one from jaycar that MRSPL suggested. I tried the unbridged channel on the sub too but like that it's basically like having no sub at all so I'll keep the amp on low settings untill I can afford that other amp. So should 4 gauge be enough to power that new amp? Thanks

4 Ga will be fine for the new amp

Yep, you should be set.

Just use the 4 channel for any speakers you have and use the monoblock for the sub. I guarantee you will will easily be able to hear the difference.

The OP is after the 500 rms mono block. Going by specs and experience if the OP runs that mono block on his SVC 4 ohm sub then the amp will only produce 125 rms

That seems a problem to me. I recommend the 1000 mono block or change to DVC

Hey, fixed the problem by buying the amp you recommended. That amp is definitely the best amp I've ever bought. Very clear, deeper and more accurate bass. I read the specs sheet that came with the amp and it says with my 4ohm SVC sub I should be getting 180W RMS. And another good thing about this new amp is that it has two speaker outlets which means now I'm gonna save up and get dual DVC subs with a ported box. Thank you all for your help with this. Especially MR SPL as he was the one that recommended this amp :D