Ok, does anybody know the amperage of their alternators?

I'm not sure, but base/enthusiast/performance may have a slightly less amperage than the touring/track based on the power features, etc.

Let me know! I'm trying to figure out the amperage and see if people upgrade the coil, etc.

THANKS!

 

I think we all have the same ones, and should not vary model to model...and I believe they are rated at 115A.

 

Hmm, thats not very much. Although, it can probably be upgraded to a 150-175 for a few hundred dollars.

Has anybody pushing 500+W RMS experiencing light fading when bass hits.

 

115 amp is not much? Yikes man, that's huge! My Toyota Tacoma pickup had a 65 amp alternator, and my Audi A4 (which has far more power features than my Z) has a 90 amp alternator.

I don't think you'll have a problem unless you run a *huge* system. If you start getting mild brown-out symptoms during big bass hits, you can try adding a cap to your system.

Remember that many (if not most) amps are overrated. Even if you have a system that claims up to 500 watts RMS capability, I think you'll be pretty hard pressed to actually get that much power out of it. My system has a pair of TRU Technology 2.100 amps, which add up to 600 watts RMS in my configuration. (And TRU amps are known for being underrated.) Have I ever run them that high, even at extremely high, uncomfortable volume levels? I doubt it. I'm going to hook an ammeter up to my system and crank it up past comfortable listening levels (but not distorting, of course) just to see what sort of power drain I'm looking at. I'll be surprised if it even hits 400 watts.

I think a lot of people with these big systems would be surprised if they hooked up ammeters and ran their systems at full tilt to see what sort of power is being used.

 

My old car had a 85 amp alternator in it and I was pushing a 12w7 w/ 500/1 JL Audio to it. 4 interior speakers with a 300/4 JL Audio amp to them.

the 500 is really more like 520
the 300 is more like 320

840 Watts and it DEFINETLY needed a HUGE upgrade...

the guys at HiFi Buys told me I would need something around 150amps on the alternator...

My new setup is going to be the same 12w7 with a 1000/1 JL Audio Amp (1020Watts) and the same 300/4 JL Audio amp (320)..

So thats why I'm asking...

 

I dunno. Not to nitpick, but I'm not sure those JL amps are underrated. In my experience, it's very rare to find such a thing. Don't get me wrong, JL amps are decent amps. Without bench testing them, though, I'd be hesitant to believe they are capable of putting out that much without the sound quality deteriorating, clipping, or some other negative factor coming into play.

While I'm thinking of it, here is the basic formula you can use to determine your current draw:

(volts)*(amps) = (watts)

Plugging in your example wattages up above, we get:

(13.8v) * (amps) = (840w)

That gives us 60.8 amps of current draw. So even if you were somehow able to pull the entire 840 watts out of those amps (which is unlikely), you'll only be pulling about 60 amps. What you'll need to figure out how is how much headroom you have in the stock alternator. (i.e. How much does the car need for its operation, and how much is left over for your personal use.)

Amp output aside, I'd just stick with the stock alternator. If you have problems, just get a good cap. (Like something from Batcap.) The only time you'll even come remotely close to pulling that much power is during very high decible low frequency output. That bass output is typically brief (bass beats and such), so a cap should cover it. However, if you like to listen to that stuff that has continuous, very low frequency bass tones and such that are constantly pulling amperages greater than your alternators capability, then maybe a higher output alternator could be needed. Keep in mind, though, that those low frequencies are not going to be going through your midbass speakers in your doors, only your sub which is only using one of the amps.

In otherwords, if you really want to spend your money, go for it. But I doubt you'll need it. Just get a nice cap.

 

nah joe i used to run those JL amps and they been tested actaully and are acutally putting out more power than advertised. These days I dont think any of the better companies out there overrate their stuff anymore, most wil underrate just to be safe. Plus 500 pretty much equals 520-525 etc cant really market a 513 watt amp whats the model number going to be 513/1??

 

Really? I didn't know JL was actually being real about their power output. I can't comment on their sound quality, but it's good to know that at least their power output is good. I would agree that *good* amp companies don't overrate much anymore, but the real question is: who is actually good? Names like TRU, Brax, US Amps, Monolithic, Zapco, etc. are definitely good amps. But what about JL, Avionixx, PPI, etc? I'd probably put those into the "pretty good' category. But heck, who knows. Everyone's got their own opinions.

And I definitely know what you mean about the model numbers for advertising's sake. Car manufacturer's are notorious for this with their engine sizes. They usually round *up* to the nearest liter. And unfortunately, many amp manufacturer's tend to make the model number some derivation of the max output, not the RMS output.

 

heres my general rule for car audio stuff, if you can buy it at best buy circut city etc then its crap, not worth buying. Not that stereo shop dont carry crap as well, but yea you get my drift.