# Voltage drop causing amp to clip?



## Ericruiz911 (Dec 25, 2014)

Hey guys,

I recently upgraded my subwoofers to (2) IDQ10's running off a Sundown Audio SAZ-1200D @ 1ohm. I am having some serious clipping since making the change. I turned the gain down and I should be between 950 and 1000 watts rms at the moment. I have the big 3 done on my truck and that fixed my lights dimming and alternator when I had my ID's but now its back. Lights dim and the voltage meter on my truck fluctuates constantly on bass hits. I am trying to figure out whether the voltage drop is causing the clipping and whether I need to upgrade the battery AND alternator or if I can just get away with doing an XS power D3400 on stock alternator. I have never had to deal with clipping before and I am kind of stumped on what could be causing it. Grounds are all good and I even upgraded them to make sure it was not that. I do have a high noise floor coming from the helix c-dsp so I am not sure if that could be causing it. Maybe add a noise filter between dsp and amp?

Truck: 2014 Chevy Silverado 1500 5.3L
Amps: Sundown Audio SAZ-1200D, ARC Audio 1200.6
Total watts RMS: 2200 watts


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## SPLEclipse (Aug 17, 2012)

What voltage are you dipping to?

Have you tried to turn the gain down more? If you are clipping you should notice that it goes from dropping into the 10/11v range to staying in the 12+ range with only a slight adjustment in gain to get you out of clipping. Clipping causes major voltage drop, and it's a bit of a positive feedback loop that will seriously strain the amp and your electrical system.

It's possible you have a bad or weak battery, but with a vehicle that's relatively new I doubt it unless you've been consistent pushing it to low voltage or excessively draining it.


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## Ericruiz911 (Dec 25, 2014)

SPLEclipse said:


> What voltage are you dipping to?
> 
> Have you tried to turn the gain down more? If you are clipping you should notice that it goes from dropping into the 10/11v range to staying in the 12+ range with only a slight adjustment in gain to get you out of clipping. Clipping causes major voltage drop, and it's a bit of a positive feedback loop that will seriously strain the amp and your electrical system.
> 
> It's possible you have a bad or weak battery, but with a vehicle that's relatively new I doubt it unless you've been consistent pushing it to low voltage or excessively draining it.


I would need to measure and get an exact reading. These new trucks have had battery issues from factory. Even my truck is already on its second battery because the first one just randomly gave out. I am not sure what else would be causing it to clip unless the battery is just not capable of pushing the power out (at least from my understanding of clipping). Purchased a noise filter just to see if that could be the case so it will be here Wednesday.

As far as turning the gain down, I have it set to give the rated RMS for the subs at the moment but using the gain knob in the front, if i turn it down to about half way, its fine expect on some lower frequencies.


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## FlyingEagle (Sep 22, 2017)

Put an amp clamp on the main alternator wire going to the battery and measure what is coming out during clipping. Have the alternator tested with load for total output cold and hot. From what I have read here, some vehicles have some issues with instantaneous loading from big bass hits that the alternator algorithm cannot keep on top of, of the Jeep variety, but most issues are with the alternator output at low speeds. Confirm what current your alternator can actually produce at idle and then at higher speeds like cruising down the road (1500-2500 RPM), and test this hot. Then test the current without the stereo on, and with it on playing heavy music. This will give you a baseline and current demands being put on the system. If the alternator cannot keep up for whatever reason (failure/over demand for RPM it is operating at or above operating parameters cold and or hot), batteries are then not the answer in a perfect world.


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## Garcbomber (May 26, 2017)

Stock alternator in those 145 or 160? Either way with the nannies and options these modern trucks have, you have too much for the stock alternator even at moderate volumes.

Sub amp 40x3A
Components 30x3A


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## gijoe (Mar 25, 2008)

What makes you think you have the gains set for 950 to 1,000 watts? That's pretty specific. The gain knob likely scales logarithmically, and gains are there to match the input voltage, so setting a gain knob halfway does NOT mean you have the amp set for half power. Your gain is probably too high.


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