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I'm going to be installing an amp for my main speakers and already have one installed for subs. I'm just wondering if I have to worry about my alternator keeping up and want to see what others think before putting in the second amp.

The two amps are 310 @ 2 channels and 75 @ 4 channels with fuses of 75A and 100A respectively. The watts for the amps are RMS.

I have a 2001 Chevy Impala and I'm not sure what my alternator is rated at at the moment but IIRC its 102.

Do I have anything to worry about if I just redo my Big 3? I replaced my battery with a better one when I got the subs in July so that is good to go. If I do need a new alternator then I think what I will do for now is only run one subwoofer until I can afford to buy a better alternator.

I read the FAQs but I couldn't get a clear idea on alternator power and any help is appreciated. Thanks

For the power, that is a lot of current draw IMO. You say redo your big 3, what size wire have you ran for the big 3? If you decide to get another alternator, in my experience it is usually cheaper to have your existing alt. rewound to a larger capacity.
What size fuses are on the amp? Like I said, seems like a lot of draw for that wattage. If your system is really pulling that type of power, then yes, I would recomend that you get a HO alternator.

Um, I am figuring on replacing my alternator eventually when I get subs. So how reliable is mralternator.com?

brent wrote:For the power, that is a lot of current draw IMO. You say redo your big 3, what size wire have you ran for the big 3? If you decide to get another alternator, in my experience it is usually cheaper to have your existing alt. rewound to a larger capacity.
What size fuses are on the amp? Like I said, seems like a lot of draw for that wattage. If your system is really pulling that type of power, then yes, I would recomend that you get a HO alternator.

I haven't done my big 3 yet. I never knew I could have my current alternator redone, I might have to look into that.

On the amps there is three 25 fuses on one and four 25 fuses on the other. I figured I would have to upgrade the alternator, but I'm pretty new at this so decided to ask first. Thanks for the reply.

Edit: I just looked in the manual for the 4 channel amp and it says its only rated at 45A for 4 ohms; the 100A is for 2 ohms. Would that make a difference, and also should I switch to smaller fuses because my speakers are 4 ohms? I don't have the manual on me for the 2 channel amp but I'm wondering if its the same case. Now I'm even more confused, but a little more optimistic that my current alternator is fine.

[quote="wang_chi7"]I haven't done my big 3 yet. I never knew I could have my current alternator redone, I might have to look into that.
On the amps there is three 25 fuses on one and four 25 fuses on the other. I figured I would have to upgrade the alternator, but I'm pretty new at this so decided to ask first. Thanks for the reply.
Edit: I just looked in the manual for the 4 channel amp and it says its only rated at 45A for 4 ohms]
What size power wire and fuse are you using?
And as for the speakers being 4 ohms are you reffering to the subs, cause if those are 4ohm they can be wired for a 2ohm load.

Right now only my subs are hooked up with a 4 gauge power and ground. The fuse is 75 and right now they are hooked up in 4 ohms (its a 2 channel amp and I just hooked one sub to each channel but the signal is mono.) Should I hook the subs up in parallel?

The 4 channel amp is not hooked up yet. It has 100A for a fuse but looking in the manual it says it only is rated at 45A for 4 ohms (which my mains are- I have 2 mains up front and midbass drivers for the two rears.) Should I get smaller fuses before I hook it up (like four 12A's) or just leave the 100A even though I'll never need that much- is that dangerous?

wang_chi7 wrote:Right now only my subs are hooked up with a 4 gauge power and ground. The fuse is 75 and right now they are hooked up in 4 ohms (its a 2 channel amp and I just hooked one sub to each channel but the signal is mono.) Should I hook the subs up in parallel?
The 4 channel amp is not hooked up yet. It has 100A for a fuse but looking in the manual it says it only is rated at 45A for 4 ohms (which my mains are- I have 2 mains up front and midbass drivers for the two rears.) Should I get smaller fuses before I hook it up (like four 12A's) or just leave the 100A even though I'll never need that much- is that dangerous?

I'm assuming that these are 4ohm single voice coil subs and if you want to get the full potential of your amp then yes they should be wired in parallel (if the subs can support the power... as I don't know what the subs are or what they are rated at)
As for the 4 ch. if those are the fuses it came with then don't put in smaller ones... the company did that for a reason.
From the sound of it you should be fine for now with a big 3 upgrade until you start making any major changes to the system that require more power...
Then you'll need the alt upgrade for that second amp.
Definately look into a rewire, it's a lot cheaper unless you plan on going really big later

That 4 channel amp was bought used, so I'm not positive if it came with the four 25A fuses originally though that would make sense so there wouldn't be problems with 2 ohms. I'll just leave them be. Thanks for the replies. I will do the rewiring and see if everything works out!

Recommend the big 3 in 0ga. wire so you don't need to do it again later when you decide to expand or go bigger

I figured I'd better do it with 0 gauge from what I've read. Might as well do it correctly once