Anonymous
Anonymous asked in Cars & TransportationCar Audio · 1 decade ago

Do I need a new alt. or just a deep cycle battery for my car audio system?

I drive a 1996 Olds. Bravada. The battery is in the last few months of its 5 year life (going by the date on the battery). I recently installed a JL 13w7 and a JL 1000/1 amp. This setup makes my voltage meter in my dash jump around like crazy. I cannot turn the sub volume and the radio volume too high or it voltage needle will sink down near the red and cause the radio to shut off. The amps input level is only about 1/4 of the way up. I have the sub volume set now where I can play it and not have it shut off. The voltage needle still drops kinda low when deep bass hits though. It still pounds but obviously not as loud as it could. For this system, do you think I could just add an optima battery and upgrade the big 3 or would I probably need a bigger alt? If I had the money I would simply upgrade everything. Please let me know what you think. Im not an electrical genius so thank you in advance for the answers.

7 Answers

Relevance
  • 1 decade ago
    Favorite Answer

    If your total system power is 1000 watts RMS or more, you will need to:

    1. Upgrade the alternator to a high output alternator

    2. Upgrade to a heavy duty deep cycle battery

    3. Upgrade the "Big 3" - that is to replace the power wire between the battery and alternator, the ground from the battery to the chassis and the ground strap from the engine/tranny to the chassis with at least 1/0 AWG wire.

    Failure to do this will result in you replacing them anyway as the alternator will eventually fail.

    Here is a guide that will calculate what size alternator and power wires you need http://www.datafilehost.com/download.php?file=6d26...

    You'll need Microsft Excel to use it.

    • Login to reply the answers
  • 1 decade ago

    Well adding a deep cycle battery willhelp your cause only to have more time listen to music while the car is off. The real power source is when the car is turned ON, and the alternator start to supply power to the car electrical system and recharge the battery.

    Typically, the main reason that you would want to add a capacitor to your audio system would be to gain better sound quality, especially from the low end of your system. Low frequencies require more power in order to be reproduced at the same level as higher frequencies.

    The capacitor improves the sound quality by storing electricity from the battery (which is provided by the alternator), and releasing it very quickly when the amplifiers need it. The capacitor then recharges from the battery. But if there is a power problem in the vehicle it's best to go right to the original source and upgrade the alternator

    If your lights dim either when the bass hits or when multiple accessories are turned on, the best thing that you can do to fix the problem is upgrade the alternator. In an automotive electrical system, the alternator provides all of the electricity that the vehicle uses. The battery is maintained by the alternator, and stores enough electricity to start the car and run the accessories for a short time while the engine is off.

    If a stereo system that has a high amount of current draw is added to a vehicle, this can possibly be too much of a load on the factory alternator, especially if the load is near or over the alternator's maximum output capabilities.

    Your car's alternator ampere rating determines how powerful an amplifier you can install. Multiply the ampere rating by 40%, and you'll get a rough idea of how much reserve current capacity your car's system has. Next, you'll need to calculate the approximate current draw of the amplifier you're considering installing.

    To calculate the current draw of an amplifier, multiply the number of channels by the RMS watts per channel (a 2 channel amp rated at 300 watts RMS per channel would be 600 watts). Double it to account for amplifier inefficiency (600 watts X 2 = 1200 watts), then divide by the average output Voltage of an alternator, 13.8 volts (1200 divided by 13.8 = 87 amps). Since the average music signal requires about 1/3rd of the average power in a test tone, divide by 3 (87 amps divided by 3 = 29 amps). The result is the amplifier's approximate average current draw.

    A quick way to ballpark an amplifier's current draw is to divide the total fuse value of the amp by two. For amplifiers with multiple fuses, the rating of all fuses provided with the amp must be added together. This will likely produce a significantly higher estimate than using the proper formula. Although inaccurate, this will err on the side of safety.

    Finally, compare the amplifier's approximate current draw to your vehicle's reserve current capacity to determine if the electrical system can support the amplifier.

    If all those numbers are a bit much, here's a simpler way to think about it: an alternator capable of producing 65 amperes is usually adequate for systems up to 270 X 2 watts RMS. A compact car with a 35-amp alternator can accommodate around 150 X 2 watts of power, while a Sport Utility with a 145-amp alternator can handle a 600 X 2 watt system.

    If you want more power than your alternator can service, you will have to consider having your alternator rebuilt for higher output — or invest in a high-output aftermarket alternator

    Source(s): 10 Years of Xperience Electrical Engineer
    • Login to reply the answers
  • 4 years ago

    whoa Nellie, what the heck?? You fail to mention year and model car. Most cars have a surplus of juice available, motorcycles have none. But your battery does not run anything without alternator backup. It starts the car, period. It is maintained at full voltage by the alternator and it is to remain at full charge or it is no good. Of course, if the battery dies, the engine will quit. And or, if the alternator dies, you will run app 1 hour before the battery quits running the engine. Make sense>? So, if your lights are dimming, I would blame that alternator not having enough voltage, amperage going out to maintain the system. You can get a bigger alternator to pump more juice, but the battery, I don't really think you need. Unless your battery is bad.

    • Login to reply the answers
  • 1 decade ago

    Here is the simple logic. The bigger the battery the more minutes you can run the audio system when the car is turned off.

    the bigger the alternator the more number of devices you can add and the load bearing capacity of your car increases.

    so in your case a bigger alternator is indeed the solution.

    A cheaper fix is to install a 1 farad capacitor before the audio system. That acts as a temp storage so your alternator doesn't get affected with high demanding sub-loads.

    Hope that answers your question.

    • Login to reply the answers
  • How do you think about the answers? You can sign in to vote the answer.
  • Anonymous
    1 decade ago

    I like how Electhro uses my calculations, "To calculate the current draw of an amplifier, multiply the number of channels by the RMS watts per channel (a 2 channel amp rated at 300 watts RMS per channel would be 600 watts). Double it to account for amplifier inefficiency (600 watts X 2 = 1200 watts), then divide by the average output Voltage of an alternator, 13.8 volts (1200 divided by 13.8 = 87 amps). Since the average music signal requires about 1/3rd of the average power in a test tone, divide by 3 (87 amps divided by 3 = 29 amps). The result is the amplifier's approximate average current draw."

    At least he finally got something right.

    vipergtsrk578 has full permission to use my quotes.

    • Login to reply the answers
  • Wisdom
    Lv 6
    1 decade ago

    Higher amps will help, but wiring must also be replaced.

    You should be considering your ears too. This much power is going to ruin your ear drums and your looking at many years of deafness.

    • Login to reply the answers
  • 1 decade ago

    what is the output on you speakers, you may have to change the amp to a larger output like 2000

    Source(s): son
    • Login to reply the answers
Still have questions? Get your answers by asking now.