jr07

I know I haven't posted in a while. I ran into an issue. The crossovers, mids, and highs were installed in the front part of the truck. When I gave the speakers power, it sounded horrible. I adjusted the voltage to the back speakers at the LC7i (Channel 2). It sounded great, so I assumed I could do the same thing for the front speakers. On the LC7i, Channel 1 is the signal coming from the tweeters and Channel 3 is the signal coming from the front speakers. Channels 1 & 3 have been internally summed.

With that said, I increased the voltage from lc7i using Channel 3 and the amp started smoking. I immediately turned everything off and let it sit. After it cooled down, I gave the amp power and everything worked great. Within 30 minutes, I noticed it had a little smoke.

I pulled the amp completely out in order to see what the board looked like. Just as I expected, there were some inner parts burned up. I researched and researched to figure out what the parts actually are. (The amp still works fine)



This is what I've come up with.... The parts affected are just before the speaker wire output for the front right. If I say this wrong...please feel free to correct me. The piece in the picture burned up is the filter (brown/red color), then it's the resistor or diode which is was blue, and the part with the webbed wiring is the inductor. So the pieces that burned were the filter and (resistor or diode part).

When I turned up Channel 3 on the LC7i, that's when this happened. I didn't know if the parts were defective, bad solders on the board, or if it was my fault. I called polk audio. The guy quizzed me with a bunch of questions and he ended up telling me that it sound like it was something that failed on the amp board. (I'm still not sure)

Would the internal channel sum of 1 & 3 push more voltage than the other channels? I've turned up channel 1 (from tweeters) and channel 2 (from rear speakers) all the way up with no issues. It's just a problem when channel 3 is adjusted.

All input is welcome. I will eventually get it repaired or repair the board myself if I can figure out what the parts are.

jr07

On a more positive note....

I met with the owner of a local car audio shop and got an estimate for a box build. I just don't feel like doing the box...lazy I guess? Fiberglass ($300) or MDF ($250). He wanted to fabricate my back seat mounts to raise up my seat 1.5 inch to 2.5 inches. That would cost an additional $300....I told him that I think there is a kit I can purchase. Does the 2013 supercrew have the kit to raise your back seat? I've only found a kit that is for 2003-2008.

KBT2011

Great thread, I've done a build in a 2010 F150 with SYNC before but it was non sony. I now own a 13 FX2 that has sony/MFT all that jazz. I'm considering just doing an Audison bit ten rather than getting a cleansweep plus the SSI.

flash69

I have a 2013 Platinum with Sony and MFT. I am using a Audio Control LC6i and a Rockford Fostgate 3sixity.3. My build is on DIYMA under my name in the build section. Almost ready to get things powered on.

azcoyote

Seat lift I used is here... LMI 0925SC
https://secure.dwebware.com/lmi/order.htm

azcoyote

So did you figure out how you scorched the amp? Are you bridging channels? Did you have massive input voltage? Fault in the amp to start with? I am using an AudioConntrol 5XS and I had to bring my output down to on the 5XS down to deal with input requirement of 4 or less volts to Alpines.

FYI - here is good tool for charting out your layout...
https://www.draw.io/

jr07

Amp is history...I honestly don't know what the deal with it was? I called an amp repair shop in my area and he told me you have to send it to polk for repair. He did however tell me that if a resistor is burning up, there is clearly something else going on in the amp that will lead to more problems. He was right. I unplugged my rears and used those channels on the amp for the components just to have something in my car. 3 hours later, I put my key in the ignition and here a horrible noise coming from the speakers. Even with the stereo turned off. I pull my key out and go straight to the back of the my truck and plan to disconnect the amp. The amp is smoking again. I'm pitching the piece of garbage and getting another brand.

I also ordered the rear seat lift kit from LMI Welding. Waiting for it to get shipped. Guy at the audio shop told me I would definitely save a lot of money by doing it that way.

Also talked about the box. the box will be tuned at 35 hertz with both 8's under the rear driver side. Box will run across the length of the truck with a port cut horizontally on the rear passenger side. It basically will blow under the pass front seat. The subs will be flush mounted into the box.

The shop I've been in contact with is also going to tune the entire system using an oscilloscope.

jmdavis333

Your post has been a wealth of information. Do you have any updates, it's been awhile?

jr07

Well....all this time has passed and still no end result of a sound system.

I put it in a shop, who has a great reputation, and decided to purchase another amp through the shop. He's an authorized dealer for rockford..(T400X4ad) great little amp. He goes to tune the system and amp....burns it up..I go there and work with him on a friday night...there is a huge surge of voltage 29.8 volts something crazy. In that process, both back speakers locked up. Another amp burns up!! We thought the problem was the LC7 i have..(The lc7 is internally summed) When channel 3 is adjusted, that's when each amp goes into protect mode. We send the LC7 into AudioControl for testing. They tell us the LC7 is ok. He's run all kind of test with an oscilloscope. Channel 3 is the input signal coming from the front door speakers. I open up the center console and let him look over all my work...he tells me everything looks good and done properly. The only thing we can come up with is that the factory amp has an issue. If that's the case, I'm thinking I possibly could have shorted the wires when I was crimping all the speedwire at night. I wanted to bypass the factory amp, but quickly realized you lose volume control functionality (unless i spend like $800 on another peice of equipment). I also looked over all my wiring ran to make sure it didn't get sliced somewhere and is grounding out (everything looks good). Owner of the shop is getting pissed off bc he's done 6 installs on trucks exactly like mine....In all this frustration, I have installed a sound system on my boat and on my brother's 4-wheeler. My truck has cooked a total of: 4 amps, 4 rear coaxial speakers, and 2 tweeters. It's just crazy....

jr07

It is with great relief and pleasure that I annouce this build is complete!

It only took around 9 months....

For some reason, my ford sync system pushes a really jumpy signal on an oscilloscope. With the LC7i, we added resistors and checked out what the wavelength looked like. It definitely cleaned up the signal. Found out they have a shop who charges $1,500 if you are trying to install aftermarket equipment to the original factory head unit/nav/sync system. Probably because they went through what I did at one point....

I ended up removing the LC7i from the equation. After talking with the shop owner, decided to upgrade to the rockford 360 processor. It's a game changer. It conditioned the input signal, which used to look terrible on the oscilloscope. It also allows you to do some serious customizing of the sound quality. The processor comes with so many features. It has a usb port on the unit, which allows you to plug into a computer and use the software to adjust each speaker. It also comes with a remote with presets; that allows you to preset for different genres of music with the click of a button. It also allows for time alignment...I'm pretty impressed with the functionality.

Got the box installed....looks great....even better the sound of the final product.

I'm gonna take pictures of everything tomorrow. I've let a couple people hear it and each has said it's the most clear sound system they've ever heard. Pretty stoked.

I also got the tonneau cover installed (F1 bakflip). This allows me to gain the storage I lost under my seat.