Which Amp Alternator ?

[ensoniqman]

Newbie question:

I have recently installed 4 amps in my 4th gen Ram truck.

The total wattage RMS is running about 1350 watts
(Front speakers, rear speakers, mids, tweeters and two subs)

Should I confirm if the alternator is 180 or 200 amp? It is factory OEM.

Or is wattage not a major concern at 1350 watts needed?

 

[ctechbob]

You're not running around with the system cranked to full tilt, so your actual current consumption will be smaller than you might think. The OEM alternator will be just fine.

Even with the system louder than would be comfortable, you're still not pulling max power. Music is dynamic, so your average current draw is much lower than RMS ratings would suggest.

 

[ensoniqman]

So no need to worry about an additional cap for power ?

 

[ctechbob]

So no need to worry about an additional cap for power ?

Capacitors don't provide any extra power. They simply smooth out the power supply to the amp. Problem with most of them these days is they're high ESR junk and don't work as well as some of the older ones.

That being said, there's no real downside to adding a cap other than cost.

 

[ensoniqman]

Thanks for the info !

 

[ctechbob]

Thanks for the info !

Lol, no worries. It's just one of my past lives.

 

[D1dad]

If you have the newish regulated charging system, it wouldn’t matter if you put an alternator from an earth mover. About the only time mine actually charges to its full capacity is idling or coasting. Or the 1st start of the day.

 

[FoxProTwisty]

You're not running around with the system cranked to full tilt, so your actual current consumption will be smaller than you might think. The OEM alternator will be just fine.

Even with the system louder than would be comfortable, you're still not pulling max power. Music is dynamic, so your average current draw is much lower than RMS ratings would suggest.

Took the words right out of my mouth.

An alt is rated at max power just like an amp. In the event your vehicle is struck by lightening or you listen to test tones recorded at 0dB RMS, it aint going to produce it.

 

[BrendanC]

i would be looking into aftermarket alternators. factory alternators may be 180-200amps but that is cruising RPM and not hot idle. Mechman can take care of you, they build probably the best aftermarket alternators. solid voltage is the key to long living amplifiers and speakers. high output alternator stops voltage drop which stops distortion if you have your stuff set correctly.

i would also look into a supplemental battery in the back close to the amps. this will help with voltage drop over your power wire on instantaneous loads (subs)

for transparency i run 1800w RMS in my pickup and i have a 370amp mechman alternator set at 14.8v hot. 2 group 34agm’s under the hood with a XS power agm behind the back seat all wired up with 2/0 welding cable.

 

[4WD]

Often the factory police units carry a larger output …
Be worth checking …

https://www.stellantisfleet.com/ramtrucks/ram-1500-ssv.html

 

[thastinger]

1350 watts is 96 Amps assuming a 14VDC output when the vehicle is running.

 

[repairman54]

Ohms law. Amps x volts = Watts. Use it in either direction.

 

[meep]

Rather than a cap, I wonder if anyone has tried mounting a small aux battery with high CCA near the amp. A battery right there does more to combat voltage drop than a stiffening cap, which can’t *sustain* voltage, just smooth it. Or, even both. That’s be pretty neat to dry. An AGM jet ski battery from Walmart would be ideal. Small, good burst current, won’t leak…

 

[BrendanC]

Rather than a cap, I wonder if anyone has tried mounting a small aux battery with high CCA near the amp. A battery right there does more to combat voltage drop than a stiffening cap, which can’t *sustain* voltage, just smooth it. Or, even both. That’s be pretty neat to dry. An AGM jet ski battery from Walmart would be ideal. Small, good burst current, won’t leak…

i have exactly that, XSPower AGM mounted by my amp rack tied in with 1/0 through a 250amp fuse to the main power buss.

 

[meep]

i have exactly that, XSPower AGM mounted by my amp rack tied in with 1/0 through a 250amp fuse to the main power buss.

Have you found that to be more effective in real use?

XPower makes excellent batteries!!

 

[BrendanC]

Have you found that to be more effective in real use?

XPower makes excellent batteries!!

absolutely. i think in a perfect world you also have a good quality cap in parallel for the super punch loads but it works much better, stopped my lights from dimming before i upgraded to a 370amp alt.