Subwoofer randomly fluctuates up in volume.

[BellyRash]

Hey, all

I recently just installed an Alpine type S 12" sub in my 2013 Ford Police Interceptor.

While I'm driving, the sub randomly spikes up in volume, and then does back down again. There's no coherent pattern that would link it to acceleration or braking.

Some context:

Ive got a Clarion XH5210 2 channel Amp with a max output of 340W. The amp's remote wire is spliced off of my accessory 1 wire from my ignition switch, as I have a stock head unit. I also have an LC2i, which receives input from my rear speakers, and then through RCA, connects to my amp. Both are off the same power cable ran from the battery, and off the same ground which I have screwed into the metal frame in my trunk. All my wiring is 14 gauge speaker wire (except power and ground of course). 

If anyone has ran into similar issues, help would be much appreciated!

- Jon

Click to read more...

 

[realflow100]

could be a ground loop with the RCA connections thats intermittent or something

if you have a bass/subwoofer knob maybe get it replaced it could be faulty 

ground loops can cause all sorts of issues. noise. volume changes randomly. buzzing. distortion. subwoofers and speakers popping.

 

[Boomin_tahoe 5,000+ posts]

Try a diff ground location for the amp. Electronics are picky and can cause noises if the same ground is used for more than 1 source.

Also is that 340 peak/max power or rms? Yes there's a difference. Peak power doesn't mean squat.

 

[BellyRash]

could be a ground loop with the RCA connections thats intermittent or something

if you have a bass/subwoofer knob maybe get it replaced it could be faulty 

ground loops can cause all sorts of issues. noise. volume changes randomly. buzzing. distortion. subwoofers and speakers popping.

I'll have to look into that. I don't have a knob for my sub; Just the on board Head Unit EQ.

Is it possible it could by my ground in my trunk has a different potential than my head unit's ground?

 

[BellyRash]

Try a diff ground location for the amp. Electronics are picky and can cause noises if the same ground is used for more than 1 source.

Also is that 340 peak/max power or rms? Yes there's a difference. Peak power doesn't mean squat.

Do you mean a different location for amp and LC2i? 

And the RMS power is 160W I believe, at 2 ohms

 

[Talontsi90]

Doesnt the LC2i have a remote output? Id use that. Honestly, troubleshooting this kind of problem with out pics, or a video just plain ***** nuts. You can explain your setup to us all day long and we could guess till the cows come home as to what the issue is.

Does the sub move around at all? Maybe what you think is cutting out, is it turning away from you.

 

[Boomin_tahoe 5,000+ posts]

Do you mean a different location for amp and LC2i? 

And the RMS power is 160W I believe, at 2 ohms

Correct.

 

[8o8k!d]

There is a ASL (Automatic Sound Levelizer) feature in some cars, especially on the stock head unit.  If you do in fact have this feature, it tends to increase volume as the car speed increases.  

 

[Jeffdachef 5,000+ posts]

The stock head unit is the issue. Its garbage throw it away. The bass fluctuates randomly with the stock speakers as well. I used to drive one for work I know every detail of that issue.