Alternator compatible with stereo?
Soundiophile
05-17-2004, 10:36 PM
I just bought a 92 Sentra and have an existing stereo that I am going to put into it. What I am wondering is if I should buy a larger alternator and if so where to get one. I have searched a little online and have not found a high output alternator for sale. The stereo is:
JL Audio 500/1 (500 Watts RMS)
JVC KS-AX6500 (70 Watts x 4 RMS)
Panasonic MXE CQ-C5410U (25 Watts x 4 RMS)
Monster Power .5 f Cap
I am going to be running the front and rear speakers off the JVC amp, but as far as I know there is no way to turn off the internal amp in the Panasonic, so it will be sucking juice at the same time as the other two. Please remember that all Watts are RMS not peak. From what I have seen the alternator is either rated at 65 or 70 amps, and Crutchfield recommends only installing stereo equip. that will suck 40% of your alternator's rated output. 880 total sys. Watts / 12 VDC = 73.3 Amps.
My last car was a straight beater, so I didn't worry about that stuff, and the one prior I did kill the alternator. (probably coincidence, I didn't have the JL amp at the time.) But I'd like to not kill the alternator in this one. Sorry for the length but wanted to answer all questions before anyone started having to guess the sys. Thanks, Jason
JL Audio 500/1 (500 Watts RMS)
JVC KS-AX6500 (70 Watts x 4 RMS)
Panasonic MXE CQ-C5410U (25 Watts x 4 RMS)
Monster Power .5 f Cap
I am going to be running the front and rear speakers off the JVC amp, but as far as I know there is no way to turn off the internal amp in the Panasonic, so it will be sucking juice at the same time as the other two. Please remember that all Watts are RMS not peak. From what I have seen the alternator is either rated at 65 or 70 amps, and Crutchfield recommends only installing stereo equip. that will suck 40% of your alternator's rated output. 880 total sys. Watts / 12 VDC = 73.3 Amps.
My last car was a straight beater, so I didn't worry about that stuff, and the one prior I did kill the alternator. (probably coincidence, I didn't have the JL amp at the time.) But I'd like to not kill the alternator in this one. Sorry for the length but wanted to answer all questions before anyone started having to guess the sys. Thanks, Jason
sr20de4evr
05-17-2004, 10:55 PM
As long as your alternator isn't shot already you'll be fine
Also, the headunit won't be drawing any power if it's not powering the speakers (ok, it will draw power to run itself, but not nearly as much as if it was powering the speakers). Make sure you tape off the speaker wires coming out of the deck though, you don't want those shorting out to each other or it will blow the amp in the headunit. Forget about the cap, it's a waste, if you have any dimming problems then upgrade the big 3, this is just some simple under-hood wiring that improves the efficiency of the stock electrical system and has atleast as much of an effect as a cap if not more. Specifically, it's the alternator + to battery + cable, battery - to chassis, and engine to chassis. Just use some 4awg wire and run it right next to the stock wire, it will definitely help.
Just for reference, I have over 1100rms in my car (just the amps, not including the headunit since it's not powering anything) and I don't get any dimming or any other electrical problems. I also have the stock 80amp alternator, stock battery, upgraded big 3, and no cap.
Also, the headunit won't be drawing any power if it's not powering the speakers (ok, it will draw power to run itself, but not nearly as much as if it was powering the speakers). Make sure you tape off the speaker wires coming out of the deck though, you don't want those shorting out to each other or it will blow the amp in the headunit. Forget about the cap, it's a waste, if you have any dimming problems then upgrade the big 3, this is just some simple under-hood wiring that improves the efficiency of the stock electrical system and has atleast as much of an effect as a cap if not more. Specifically, it's the alternator + to battery + cable, battery - to chassis, and engine to chassis. Just use some 4awg wire and run it right next to the stock wire, it will definitely help.
Just for reference, I have over 1100rms in my car (just the amps, not including the headunit since it's not powering anything) and I don't get any dimming or any other electrical problems. I also have the stock 80amp alternator, stock battery, upgraded big 3, and no cap.
shortysdrop
05-17-2004, 10:59 PM
That will be quite a load but I would switch up to a 1.0 farad cap that will help. As for the alternator I've run just a 380 watt amp and stressed my alternator before. I would probably upgrade the alternator to be safe. I've never run a factory alternator with my systems. You will be sucking a lot of juice so play it safe and upgrade. Oh and I say upgrade the cap because the .5 is rated up to 500 watts.
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