Amp getting hot since adding subs

[Nanos]

Ok guys im really a novice when it comes to car audio

I know the basics and how to wire everything.

Well i have just added 2 x 12 inch subs the wagon. I used to only have a 10inch sub and never had problem.

The problem im getting is the amp is getting hot. hot enough that you cant touch it.

the amp that is running the subs is a audioline 4x300peak(1200peak). I have it bridged to 2 channels as per all diagrams.

It is working nor problems and is driving the subs without a issue. gain levels are about 3/4. I have checked polarity to make sure these is not reversed and that is fine.

What are some causes for a amp heating up like this? I know its a cheap amp but the system is not in the car to win competitions just there for the fact its a commodore and it needs subs. lol

[HCVP]

Mate that a simple one really, your amp is under a lot more strain running 2 12's, compared to when you used to just run a single 10' off it. Even though you've set the gain to 3/4, your amp is basically working flat out 100% of the time, trying to power 2 12' subs, so yeah it's gonna get damn hot. It's always best to feed your speakers/subs, a bit more power than what they are rated are. It just means the amp can run more effeciently. Right now you'd be under powering your subs, which can also cause damage to them aswell.

[Nanos]

ok so in short new amp that is bigger than subs can handle

[HCVP]

in short yes, just think, if you have a speaker that's rated at 10 watts RMS, and you use an amp that supplies 15 watts RMS, it wont have to work anywhere near as hard to supply a stable amount of constant power, meaning it will run cooler and for longer..

[holdenboy]

Mate what impedance are the subwoofers? specs?

You may be running the amplifier at an impedance that is to low.

[camstatic]

I think you'll find your amp is a high power amplifier, not a high current. Let's say your subs are 4ohms each, wiring them in parallel will present a 2ohm load (requiring relatively high current to drive), drawing more current from any electrical source will create more heat. Bridging also requires more current due to the nature of how bridging works, and will in-turn also create more heat.

The question is, is your amp rated to supply the impedance (ohms) you've loaded it up at whilst bridged? I'd say probably not (being a 4 channel, but that's not necessarily a golden rule), but with some amps you can still get away with it, it's up to you if you want to risk maybe frying your amp or not.

+1 to Holdenboy's question, except can we also get the model number for both the amp, and the woofers as well?

[HCVP]

shouldn't matter that he's gone from running one sub at 4ohm, to running to sub's at 2ohm each, the majority of 4 channel amps on the market are 2ohm stable anyway. It's basically a cheap amp that was never intended to run 2 x subwoofers, and he is going to fry the shit out of it it no time.

[camstatic]

No he's bridged, which you'll find is more often than not, only four ohm stable.

Which means two four ohm subs (assuming they are four ohm), wired in parallel (if it were in series we'd be hearing about lack of output), which means a 2ohm load on a 4ohm rated output. Double the current.

[groberr]

ive found that generally most amps arnt 2 ohms stable if your bridgeing 2ohm stable each channel yes but not in bridged mode

[pedrotski]

most amps are 4ohm stable. dont kid yourself. especially low range amps. you are running both 4 ohms subs in parralell from the bridge. so you are running the amp at 2 ohms. put 1 sub on each channel and it will fix your problem.

[Nanos]

The subsa re connected to indivdual channels. Its a 4 channels bridged to seperate channels.

Subs are connected indivdually to each channel. I think it may have to do with being low end amp and also under power. the amp when bridges i s 2 x 600 peak, but the subs are 1200peak so i have no way enough power to drive them.

Going ot look this weekend at getting hopefully a monoblock to drive the subs.

[camstatic]

PM sent to Nanos

[| evaN |]

just remember when comparing audio equipment, compare the rms values and not their max power or peak power or any of that other crap.

[holdenboy]

Nanos - I beleive you have been misled, just because your amp isnt rated as high as you subs certainly dosent mean the amp wont have enough power to drive them, it definately will have enough power...you just wont be getting the full potential out of the subs.

Side note - If possible dont quote "max" or pmpo figures, they are totally useless as different companies use different techniques to determine the maximum output an amp / sub / speakers produce. If possible look at the RMS ratings or even better continous ratings. As a general rule if the amp / sub doesnt have these values listed in their specs or manual its best to steer clear of that brand.

[HCVP]

How healthy can it be for his sub's though only giving them half their power output..?

[acarmody]

Won't hurt the subs only running at half their rated power, as long as you don't try raising the gain to get more volume.

[camstatic]

Yeah the amp will square wave (clip) and fry them with dc voltage if he tries to overdrive it.

[HCVP]

i know this, but does Nanos? that's why i was saying to him it's always best to match an amp's power output to that of your speakers, or even a bit more.

[holdenboy]

The amp wont have "trouble" powering the subs, nor will clipping the output damage the amp at all, the subs are the one being fed a clipped signal....they will cop the damage.

The more power you give a speaker / sub, the "harder" it is to clip a signal, not saying you cant clip a signal with 2-3 times the power, but the likelyhood is slimmer.