spacer spacer spacer spacer

Will these two amps overload battery/alt?

Post ReplyPost New Topic
< Prev Topic Next Topic >
Member - Posts: 26
Member spacespace
Joined: September 16, 2004
Location: United States
Posted: January 04, 2005 at 9:08 PM / IP Logged  

This is the first question I should have asked in this forum.  I have one Hifonics Series VIII Odin (75x2 @ 4 ohms, 240x1 @ 4 ohms) and a Hifonics Series VIII Jupiter (35x4 @ 4 ohms).  I do not want to buy any new amps, but I am afraid that these will put too mcuh stress on my car's battery alternator.  (I seemed to go through too many batteries in my previous car)  Do I just need a capacitor?  If I do, what size?  I am only going to run the 4 channel to 6.5 separates up front, 5.25 coaxials or midbass in back and the two channel will be bridged to mono to run one 10" alumapro sub in a small sealed enclosure.  Looking at my owner's manual, it indicates that @ 4 ohms = typical current for 4 channel with music = 14 A - typical current for 2 channel with music =  10 A.  It lists maximum for each @ 4 ohms @ 21 A & 29 A.  It would be sweet if I could use these amps, if anyone knows if I can do it with few problems, let me know. 

aggie altima 
Silver - Posts: 298
Silver spacespace
Joined: July 25, 2002
Location: United States
Posted: January 04, 2005 at 9:14 PM / IP Logged  
It depends on what your stock alternator is rated at, but unless you have a Geo Metro, your stock alternator and battery should be fine. Also, make sure not to use your system with the engine off.
Don't like rockford subs? Then don't look at my car =)
Member - Posts: 26
Member spacespace
Joined: September 16, 2004
Location: United States
Posted: January 04, 2005 at 9:36 PM / IP Logged  
Will I need to get a capacitor?
Platinum - Posts: 2,483
Platinum spacespace
Joined: April 11, 2002
Location: United States
Posted: January 04, 2005 at 9:47 PM / IP Logged  
what type of vehicle is this going into? More then likely you will not need a capicator
2009 0-1000 Trunk WR 154.0DB 2009 1001+ Trunk WR
2007 USACI World Champion
2007 World Record
2006 USACI Finals 2nd Place
Silver - Posts: 328
Silver spacespace
Joined: October 11, 2004
Location: United States
Posted: January 04, 2005 at 9:59 PM / IP Logged  

Capacitors really don't solve the problem in most cases..You should really read a little bit about what capacitors actually do. I have no clue why the two amps your talking about would put any sort of toll on your stock electrical system. I know of people running 1000+wrms on their stock alts with no problems. Upgrade to a deep cycle battery. That should be more helpful than a cap. Id reccomend the Optima Red Top. That will probably be my next battery.

Pioneer Premier DEH-P660
15" Kicker CVR
Profile AP1000M
It's Loud
Member - Posts: 26
Member spacespace
Joined: September 16, 2004
Location: United States
Posted: January 04, 2005 at 10:23 PM / IP Logged  
Thanks for all the replies...This is going into a 2005 Subaru WRX STi.  I thought I would need a capacitor because in my last car 1995 Nissan Maxima - the lights would dim when the music hit.  Second reason I thought I would need a capacitor or something is because a car audio shop said...#1 I would need one....and #2 tried to sell me different amp.  Idea was that my amps were old technology that ate up too much current to produce their power.  I did not have anyone else to ask before this forum.  I really liked my amps, but I started to believe them. 
Platinum - Posts: 5,816
Platinum spaceThis member has made a donation to Click here for more info.spaceThis member has been recognized as an authority in Mobile Audio and Video. Click here for more info.spaceThis member consistently provides reliable informationspace
Joined: January 24, 2004
Location: Pennsylvania, United States
Posted: January 04, 2005 at 11:41 PM / IP Logged  
1.  If I were selling caps for a profit I would make sure you had one, too.  That's just business, but this forum is real world.  2.  The good manual that you quoted from is taking efficiency into consideration when they give you those specs.  It is true that you can get better efficiency by trading out the sub amp for a class D mono amp, but with every improvement on one end there is always a trade-off on the other end.  You should do your best to keep those Hifonics amps working for you.  The first thing you should do is upgrade the power wiring in the engine bay:  battery ground to chassis, alternator to battery, alternator (body) to ground.  Just replace existing factory wiring with beefy new wire and sanded, clean ground points at original locations.
Copper - Posts: 34
Copper spacespace
Joined: August 21, 2004
Location: Australia
Posted: January 05, 2005 at 12:57 AM / IP Logged  
I dont think you will have much of a problem if ur going with an '05 REX. My uncle has a '03 model and is running twin 12" Type R's in it with a set of splits up front and a set of coaxils in the rear with appropriate amps, nd he has a stock alt and doesnt have any trouble with it at all! I have one question for you tho, with the old car were you running the stereo with the car off, koz if u were that would make short work of any battery. But yea, i recon wait and see how you go with the new car, hav it all running 4 ga power and ground etc, but yea i dont see why you would have any trouble.
       ~* Cheer Nat *~
Pioneer DEH-7650MP
Pioneer TS-C160R
Pioneer TS-A6990S
Pioneer GM-6000F 4ch Amp
Audiobahn AW120T 12" Sub
Pioneer GM-D510M Mono Amp
AERPRO 1F Capacitor
Copper - Posts: 103
Copper spacespace
Joined: January 05, 2005
Location: United States
Posted: January 05, 2005 at 6:11 AM / IP Logged  
Rule of thumb is 1 farad cap for every 1000 watts. I 've only seen lights dim in old cars or cheap a$$ cars like Hyundais. I'd recommend an Optima Red Top, and that should be it.  If the alt used ti dim in your old car, more then likely you had  a bad alt.
Silver - Posts: 880
Silver spacespace
Joined: May 20, 2004
Location: United States
Posted: January 05, 2005 at 11:20 AM / IP Logged  
I agree with what everyone else said. That alt. is probably at least 90amps, possibly more (it should say on the alt. somewhere if you are really curious). A cap doesnt really help to much, and in fact willl hurt you if you dont already have a good charging system (ie. HO alt. and a deep cycle battery.) Also, I would recommend a optima yellow top rather then a red top, they tend to be a little better for car audio applications.
Page of 2

  Printable version Printable version Post ReplyPost New Topic
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot delete your posts in this forum
You cannot edit your posts in this forum
You cannot create polls in this forum
You cannot vote in polls in this forum

Follow Follow on Facebook
Saturday, January 28, 2023 • Copyright © 1999-2023, All Rights Reserved Privacy Policy & Use of Cookies
Disclaimer: *All information on this site ( ) is provided "as is" without any warranty of any kind, either expressed or implied, including but not limited to fitness for a particular use. Any user assumes the entire risk as to the accuracy and use of this information. Please verify all wire colors and diagrams before applying any information.

Secured by Sectigo spacer spacer spacer
Top spacer spacer