Big 3, AGM battery & high output alt....Lights still dim

[SoldOner]

I have a 2000 altima running running a Hifonics HFi1500D pushing 2 kenwood KFc-w3012s @ 2ohms

When i First had the amp installed i could only have it a 1/3 gain. The voltage drop was so severe it caused the rpm to drop and stall the car out. So figuring i needed more than just a battery and big 3 i bought a singer 220a alternator. I turned the gain to about 3/4 but it still dimmed so i went ahead with the big 3 (2g) & put a Duralast platinum AGM battery under the hood. At this point im lost. The Rpm stays solid but the cars lights dim more than ever. My amps display light (HF) has a constant flicker to it too as if its not getting constant flow of power or something.

My friend has the very same amp in is grand marquis. His system hits atleast 3 times harder with stock electrical with almost no dimming at all.

Im lost at this point. Any ideas what the issues could be with the dimming and flicker even with all the supporting mods?

Thanks Much!

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[fatboytyler]

First off, the gain knob isn't volume. Have you checked all the connections? Sounds like it may be a bad ground somewhere.

 

[SoldOner]

Yes I'm aware that the gain knob isn't volume. I have replaced the amp ground with 4g cable and rechecked the big 3 and all wires to/from the amp. I was thinking bad ground too but I don't know where else to check.

 

[LosIsATool 5,000+ posts]

Clipping will cause dimming

 

[CSCStang]

You're clipping man. How did you set your gains? By ear? What's your voltage drop reading on heavy bass hits?

 

[Jeffdachef 5,000+ posts]

Yes I'm aware that the gain knob isn't volume. I have replaced the amp ground with 4g cable and rechecked the big 3 and all wires to/from the amp. I was thinking bad ground too but I don't know where else to check.

Check your alternator to see if its working or has a loose connection somewhere. Also with a high output alternator, sometimes you have to buy a smaller belt due to the smaller overdrive pulleys they use. If you dont use the proper belt size you'll have significantly less output amperage then even stock.

It could also be that your car body/frame is not a suitable enough ground, very rare but some cars have that problem. If it is that then you'd have to run a dedicated 0 gauge ground run from the battery to the back. Before that though, use your multi-meter to check resistance at each connection, gotta pinpoint your weakest links.

 

[SoldOner]

I'm running the stock rado so clipping is definitely a real posibility. I try to keep the volume at a level that doesn't distort.

I set the gain by ear. Listened for the slightest audible distortion and backed it down. I'll have to find our meter & check the voltage & drop.

I put an inch shorter belt on when I installed the alternator & checked everything again when I did the big 3. Will check the connections with a meter as we'll.

Thanks for the help. At least I have an idea where to start.

It may just be the car. I had a system in my last car with no problems.

 

[CSCStang]

I'm running the stock rado so clipping is definitely a real posibility. I try to keep the volume at a level that doesn't distort.
I set the gain by ear. Listened for the slightest audible distortion and backed it down. I'll have to find our meter & check the voltage & drop.

I put an inch shorter belt on when I installed the alternator & checked everything again when I did the big 3. Will check the connections with a meter as we'll.

Thanks for the help. At least I have an idea where to start.

It may just be the car. I had a system in my last car with no problems.

Yeah, start testing. You can clip your signal before it's even audible. Are you running a loc or high input to your amp?

 

[SoldOner]

Yeah, start testing. You can clip your signal before it's even audible. Are you running a loc or high input to your amp?

Im running an Loc to the amp. i need an aftermarket headunit but i keep having to put it off.

 

[Jeffdachef 5,000+ posts]

Im running an Loc to the amp. i need an aftermarket headunit but i keep having to put it off.

yeah stock head unit and LOC are not a very clean source. I would not set this system up without an oscilloscope because you are dealing with the gains of the LOC along with your amp gains so its a very delicate subject. Along with the limited bass eq functions of the head unit.

 

[mlstrass 5,000+ posts]

I'm running the stock rado so clipping is definitely a real posibility. I try to keep the volume at a level that doesn't distort.
I set the gain by ear. Listened for the slightest audible distortion and backed it down. I'll have to find our meter & check the voltage & drop.

I put an inch shorter belt on when I installed the alternator & checked everything again when I did the big 3. Will check the connections with a meter as we'll.

Thanks for the help. At least I have an idea where to start.

It may just be the car. I had a system in my last car with no problems.

It's NOT the car, you have something wrong as mentioned. My guess is gain way too high, clipped signal will cause bad dimming with the electrical you have.

I ran 28kw in a 2000 Altima off 1 DC 270 and 16 batts and had ZERO dimming....

 

[tc300 10+ year member]

a clean signal and source is KEY to a good system... should always start there before amp(s) and sub(s)

 

[fatboytyler]

What kind of music are you listening to? If you download it off the interwebz it could be that you're playing too dirty of music that is also causing the clipping.

 

[rfluvinmf 10+ year member]

Since you are using 2ga as power wire, you should upgrade your ground to that size or larger.

 

[SoldOner]

Im gonna get a new headunit soon as i can. this stock unit has run its course. I wish i had access to an O scope lol, woundnt be having these issues.

The gain could be too high but it doesnt make sense that its gotta be at such a low level with all these things supporting the amp. guess im gonna retune this thing again.

Most of my music i get off the internet. i try to download in the highest quality available.

Power wire from battery to amp is 4g, amp ground is 4g & big 3 is 2g. I would use 0g for everything but it wont fit in the amp terminals.

Im going to get into everything with a meter once the weather clears up. If i cant figure it out ill have to take it somewhere with an o scope & have it set up properly.