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Discussion Starter #1
I've had this car a while now and I've been having somewhat of a major audio issue lately. I have the non sony stock radio with Sync that is going into an LC7i which then is going into a RF 1000x something or another 5 channel amp which then goes into the speakers. I am pretty sure that the speakers all at 2 ohms, front speakers, rear speakers, and 12 inch woofer.

My issue is this: I generally play music through my iphone thru the bluetooth. What is happening is that the radio will quit outputting sound randomly and then never come back on again. no sound bluetooth or when I turn on regular radio. The radio itself is on and never loses power. It never freezes up or anything like that. Just a loss of sound. IF I turn the car off and back on, it does not come on. It will, however come back on if I disconnect the battery. I thought maybe it was the LC7i, because a while back, someone broke into my car and tried to yank it out but failed to do so. I guess it could be something in the unit was damaged. The only thing I haven't tried is disconnect the power from the LC7i and plug it back in to see if it works, but I didn't think it was this since the LC7i powers down when the car is turned off anyway.

Has anything similar happened to anyone else? I was reading somewhere that the amp or LC7i could be drawing too much power from the radio and causing it damage, I thought about this since the speakers are wired to 2 ohms to the amp and the possible theft damage to the LC7i. From what I under stand, the LC7i takes the incoming power from the radio and outputs an even output into the amp. The LC7i is being powered from an empty fuse spot from the box in the driver side rear. The LC7i was supposed have auto turn on power from the speaker level inputs, but I guess the power coming from the radio is not strong enough to turn it on, because that did not happen for me, hence why I have it powered from the fuse box. I do not remember this happening before the would be thief tried yanking out my LC7i from the glovebox.

I am not an electrician by any means and I installed it myself. For those interested, my set up is the Audiocontrol LC7i, Rockfod fosgate 1000x? 5 channel amp, going to RF comps to the front doors and RF speakers in the rear doors, and a RF punch stage 2 12 inch sub in the back corner, with the amp mounted to the sub box, allowing the spare tire to stay. Speakers and Sub at 2 ohms.

Thanks for taking the time to read all of this. If its the LC7i, I was thinking about just ditching it and getting an aftermarket head. I just like the factory look and keeping the steering wheel functionality. Car is 2014 with 180k miles on it, daily driver.
 

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When you have no sound you have to check the devices for power or any fault lights if equipped. That is the only way to start troubleshooting.

you may also want to double check all connections you've made to make sure all is properly crimped/soldered and generally solid and reliable. I personally love ferrules on my amp connections too. Makes the connection bulletproof
 

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Discussion Starter #3
I feel good about all the connections, I soldered them all when I originally installed. But you are right, maybe this weekend I can pull off the radio and check between the radio and LC7i. It just seems strange it is fixed by disconnecting the battery. I feel like my radio is going bad or the LC7 is pulling juice from the factory head.
 

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2017 Kona Blue ST1
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How exactly did you determine the point where the factory high level outputs began clipping?

Will this only happen with Bluetooth or can it be replicated with other audio signals?
 

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Discussion Starter #5
There is no clipping, the sounds just stops, there is no sound, it doesn't make a popping sound or anything. It usually happens with the bluetooth, as that is normally what I listen to, but when switching to the radio, it also does not work. It also seems to happen at higher volumes, but not that high. THe last time it happened, the volume was at 22 or 23. I tuned it so even at max volume on the radio, the sound does not distort or anything, as I did not want to run a hot amp or blow speakers, etc.
 

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2017 Kona Blue ST1
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Ok, clipping is where the AC sign wave is extended past a point where the top of the sine wave is cut off, or clipped. You could see this on an oscilloscope.
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This clipping is the audible distortion you would hear in an unbalanced system. The reason why I asked about the bluetooth was you are now not only dealing with the volume control level of your factory head unit but also the bluetooth volume from your cellphone.

My factory head unit distorts well before 23 and it's a 2017. So if I'm skating the line of clipping at, let's say 22 at all my desired frequency ranges then 22 is now considered my new 100% volume.

At my loudest setting (22) I know that if I play Samsung S20 above 2/3rd bluetooth volume my signal will begin to clip again. So now I know what to set my phone to and how loud I can turn my factory head unit. The ACM will shut itself down to protect itself against damaging if heat becomes an issue.

The age of the ACM is another factor as well.

So how exactly did you determine the audio outputs of your? DDM? Oscilloscope? When it shuts down can you scan for any trouble codes like a "U" code (communications error)
 

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Clipping can put an amp or even an advance signal processor into a shutdown mode. So gain adjustment is one of the key things to setup properly.

you can do the simple voltage method to set the gain, an oscilloscope is even better. There are even cheap DMM’s that can do both. I have one that is $30 and i ised it for that very purpose
 
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