Subs intermittently sound bad

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Nerdles1

Full Access Member
Joined
Jul 3, 2017
Posts
258
Reaction score
76
Running pac audio AP4-FD31 to JL rd 1500 to 2 jl13.5 subs all was good for years. Took to dealer for oil change and told them I had some noise sometimes at low speed in left front tire could be bearing. Any how came back from dealer seemed like my subs were cutting out and sounding like garbage occasionally. The amp stayed on while this was happening. Figured maybe amp was blowing I replaced the amp seemed ok for a hour or so and then acted up again. I thought maybe pac ap4 could be bad swapped it out for another still same result. Could my speakers be blowing or slightly blown? Any way to test them? All is good at times and then acts up. Anyway back to something the dealer said that doesn’t make sense they said I have 2 positives running to my sub output and that could be what is making the noise I’m hearing in the wheel. Why would they say that?1. Subs are not connected to stock speaker wires. 2. They would not touch anything aftermarket. 3. How would they even test that and why?
I think they had some fun turning up the volume blew my crap up and then said that to cover their ass. Thinking about putting my subs in my wife’s truck to test them and see if it does the same.
 

HighwaySentinel

︻デ┳═ー - - - - - - -
Joined
Dec 13, 2020
Posts
1,788
Reaction score
3,923
Location
California
Definitely suspect that they are giving you information on your sub outputs when you asked them to fix a noise in your front wheel area.

To test your subs, grab your multimeter and watch this video. Useful info begins around the 1:30 mark.

 
OP
OP
N

Nerdles1

Full Access Member
Joined
Jul 3, 2017
Posts
258
Reaction score
76
Thanks didn’t realize was so simple. Gonna test tomorrow. Thinking they heard the wind up feedback when you just start the truck cause my gains are set a little to high. Anyhow I’m in an amp I didn’t need may be able to return. I’m hoping I don’t have an input problem from the head unit. If it’s bad there’s no way they would warranty with aftermarket setup.
 

SoundsGoodStereo

F-Series Stereo Specialist
Supporting Vendor
Joined
Dec 2, 2020
Posts
124
Reaction score
166
Location
Nashville, TN
Make sure you check your ground/power connections at the battery. If you used the rear wall for ground, the glue joints could have released enough to cause these issues. If you haven't already, run the ground to the battery. Also, make sure the power/ground of your PAC uses those connections and not the factory power/ground. If ground is good, then the dealership might have got carried away with your system and blew the subwoofers.
 

Shane361

FRF Addict
Joined
Aug 3, 2021
Posts
1,787
Reaction score
3,488
Location
Charleston, SC
How do you know your gains are set too high? FYI a gain is not a volume knob. Litterally the biggest misconception in mobile audio. There is one spot that gain is suppose to be...just one. I have a DD1 and an Oscope to set mine and I like the 50.00 Oscope better. First you need to understand where your head unit clips or distorts at. My 2020 Raptor is at 37..so with the volume at 36 and my bass knob at 100% I tune my gain knob just before clipping.
 
OP
OP
N

Nerdles1

Full Access Member
Joined
Jul 3, 2017
Posts
258
Reaction score
76
Yep I agree just hadn’t spent the time setting it correctly. The highest volume I could physically take was at 25 but still didn’t clip out or distort. Had it set lower before so volume went higher also no engine noise at start up(mainly on 4 channel amp). I also made the mistake with the sub amp of not setting it at max right before it clipped. I listen to all kinds of music and Van Halen lets you crank up the bass without clipping compared to Kanye songs. So someone other than me could turn the knob up and do some damage to system. Also thanks for the tip SGS and yes I have a straight run to the battery can’t remember how I supplied the ground to pac but I will check. Everything has been perfect till I got it back from dealer so just bummed I might be buying another set of 700 a piece speakers again
 

Shane361

FRF Addict
Joined
Aug 3, 2021
Posts
1,787
Reaction score
3,488
Location
Charleston, SC
Another good FYi below the rear seats on either side under the carpet are two roughly 6 inch plastic plates. Amazing for running cable through. I keep my 112ah of Headway Lithium in the bed so I run cable from the alt to it in the bed then into the cab through those plastic plates. Also ground to the alt lower bolt and the frame. Amps are grounded to battery.
 
OP
OP
N

Nerdles1

Full Access Member
Joined
Jul 3, 2017
Posts
258
Reaction score
76
Tested the resistance today and on both subs they are the 2ohm models. One was at 2.4 the other was at 3.5-4.0 so I am sure something is wrong. I cannot get the dang screens off to push test them. I disconnected the one reading bad. Gonna roll with one sub to test for a while to see if things crap out. Got to say even one sub rocks gonna be hard to spend that 7 hundo for another.
 
Top