stupidly powerful audio system - small, weak engine/alternator/battery?

Question

i have two 3000watt amplifiers, one for my two 1000watt 6x9s and one for my 3000watt subwoofer - im running the 6x9s but am scared of using sub in case my car dies and I get stuck somewhere.
I hear i may need a 'power-cap' or something but do not know which one i need, or how much they are, or how theyre fitted or what the hell they are! any help?

i have a 1992 1.8litre diesel engine - would that be sufficient if I only had music on with the engine running. How much would it affect my acceleration and would a power cap help solve this problem?

Answer 1

This is simple Ohms law. Volts times (x) Amps = Watts. You're probably talking about "peak" Watts here. Ignore "peak" and look at RMS power. Class A/B amps are commonly only 40 to 60 % efficient at full power. Class D amps are commonly 60 to 70 % efficient. So (as an example), for 2000 WRMS of output, your power delivery system needs to feed the amps 2800 Watts which, at 13.8V common running voltage, is 202.9 Amps. Your factory alternator probably only charges at a maximum of 100 Amps (check your owner's manual for specifics). And, this doesn't include the roughly 50 Amps of current required to just run the electronics of your vehicle. That's over 250A of alternator power, just to keep from pulling from a low voltage, discharging battery.

Short answer: No -- your electrical system cannot sustain that kind of actual power.

Cap's won't do anything real to help you. Even with very rare and expensive, extremely low ESR electrolytic caps, you'd need hundreds or thousands of 1F capacitors to do anything meaningful for your system, and even that is debatable. The common carbon cap's you see everywhere have never been actually proven to provide any benefit. Save the money and invest in high-output alternator and excellent cabling and connectors.

Answer 2

idk

But the purpose of power is definition, not volume. A high powered system works best when you're not using all that power. Do that and your neighbours will not kill you. A 6k rig like you have is enough for a rock band in a rather large night club. Outdoors, it would be run on standalone generators with alternators that are rather larger than the one under your bonnet. Indoors, it would need its own dedicated circuit.

Answer 3

A power cap is another name for a Capacitor, what it does is stores power, so that when you have the amps on full as opposed to draining the battery from source it drains off the capacitor. It fits inline between battery and amp. They range from about 50 odd quid up depending on how much power they can store. You shouldn't have a major issue as is to be fair, as long as you only crank it up whilst driving and don't sit in MacDonalds or somewhere blasting music with the engine off.

Answer 4

A power cap is a large capacitor that charges up while the car is running and aids the battery, It is in essance another battery for you amps that will reduce the risk of you flattening your battery while you listen / shake your car to bits with your sub.
Try looking at maplin.co.uk at their car audio section.

Answer 5

uprate the alternator and get a second battery wired in, but until then dont run it with the engine off and if its as powerful as you say i hope you have it all fused with very beefy cables.

Answer 6

You have two 3000watt amplifiers, one for your two 1000watt 6x9s and one for your 3000watt subwoofer -
In a car..............why? They annoy everybody and must distract your driving.

Answer 7

Read and Digest how HiAmp has replied to your question. Absolutely accurate, and very well worded. That man knows his onions. Respect!

Answer 8

You're pulling more power than your electrical system can handle.

Answer 9

ahahahahah, 1000 watt 6x9, what are they pyle, or rockwood hahahahaha

Answer 10

not wishing to blow sunshine up his a*se, but Hi-Amp has it in a nutshell!